diff --git a/composer.lock b/composer.lock
index 48b3ba21a6..3928c319bc 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,7 +4,6 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#composer-lock-the-lock-file",
         "This file is @generated automatically"
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@@ -48,7 +47,7 @@
                 "cors",
                 "stack"
             ],
-            "time": "2016-08-01 12:05:04"
+            "time": "2016-08-01T12:05:04+00:00"
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@@ -143,7 +142,7 @@
                 "zend",
                 "zikula"
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-            "time": "2015-02-18 17:17:01"
+            "time": "2015-02-18T17:17:01+00:00"
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@@ -204,7 +203,7 @@
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                 "versioning"
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-            "time": "2015-09-21 09:42:36"
+            "time": "2015-09-21T09:42:36+00:00"
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@@ -272,7 +271,7 @@
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                 "parser"
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-            "time": "2015-08-31 12:32:49"
+            "time": "2015-08-31T12:32:49+00:00"
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@@ -342,7 +341,7 @@
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-            "time": "2015-08-31 12:36:41"
+            "time": "2015-08-31T12:36:41+00:00"
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@@ -408,7 +407,7 @@
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                 "iterator"
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-            "time": "2015-04-14 22:21:58"
+            "time": "2015-04-14T22:21:58+00:00"
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@@ -481,7 +480,7 @@
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-            "time": "2015-08-31 13:00:22"
+            "time": "2015-08-31T13:00:22+00:00"
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@@ -548,7 +547,7 @@
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                 "string"
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-            "time": "2014-12-20 21:24:13"
+            "time": "2014-12-20T21:24:13+00:00"
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@@ -602,7 +601,7 @@
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                 "parser"
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-            "time": "2014-09-09 13:34:57"
+            "time": "2014-09-09T13:34:57+00:00"
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@@ -664,7 +663,7 @@
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-            "time": "2015-02-27 09:45:49"
+            "time": "2015-02-27T09:45:49+00:00"
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@@ -717,7 +716,7 @@
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                 "validator"
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-            "time": "2015-06-22 21:07:51"
+            "time": "2015-06-22T21:07:51+00:00"
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             "name": "guzzlehttp/guzzle",
@@ -779,7 +778,7 @@
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                 "web service"
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-            "time": "2016-07-15 17:22:37"
+            "time": "2016-07-15T17:22:37+00:00"
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@@ -830,7 +829,7 @@
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                 "promise"
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-            "time": "2016-05-18 16:56:05"
+            "time": "2016-05-18T16:56:05+00:00"
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@@ -888,7 +887,7 @@
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                 "uri"
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-            "time": "2016-06-24 23:00:38"
+            "time": "2016-06-24T23:00:38+00:00"
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@@ -930,7 +929,7 @@
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                 "password"
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-            "time": "2014-11-20 16:49:30"
+            "time": "2014-11-20T16:49:30+00:00"
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@@ -995,7 +994,7 @@
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-            "time": "2016-05-10 14:11:45"
+            "time": "2016-05-10T14:11:45+00:00"
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@@ -1043,7 +1042,7 @@
                 "pseudorandom",
                 "random"
             ],
-            "time": "2016-04-03 06:00:07"
+            "time": "2016-04-03T06:00:07+00:00"
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@@ -1092,7 +1091,7 @@
                 "request",
                 "response"
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-            "time": "2015-05-04 20:22:00"
+            "time": "2015-05-04T20:22:00+00:00"
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@@ -1130,7 +1129,7 @@
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-            "time": "2012-12-21 11:40:51"
+            "time": "2012-12-21T11:40:51+00:00"
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@@ -1179,7 +1178,7 @@
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                 "stack"
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-            "time": "2016-06-02 06:58:42"
+            "time": "2016-06-02T06:58:42+00:00"
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@@ -1238,7 +1237,7 @@
                 "database",
                 "routing"
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-            "time": "2016-03-31 09:11:39"
+            "time": "2016-03-31T09:11:39+00:00"
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@@ -1291,7 +1290,7 @@
             ],
             "description": "Symfony ClassLoader Component",
             "homepage": "https://symfony.com",
-            "time": "2016-11-29 08:25:54"
+            "time": "2016-11-29T08:25:54+00:00"
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@@ -1352,7 +1351,7 @@
             ],
             "description": "Symfony Console Component",
             "homepage": "https://symfony.com",
-            "time": "2016-12-06 11:59:35"
+            "time": "2016-12-06T11:59:35+00:00"
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@@ -1409,7 +1408,7 @@
             ],
             "description": "Symfony Debug Component",
             "homepage": "https://symfony.com",
-            "time": "2016-11-15 12:53:17"
+            "time": "2016-11-15T12:53:17+00:00"
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@@ -1472,7 +1471,7 @@
             ],
             "description": "Symfony DependencyInjection Component",
             "homepage": "https://symfony.com",
-            "time": "2016-12-08 14:41:31"
+            "time": "2016-12-08T14:41:31+00:00"
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@@ -1528,7 +1527,7 @@
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             "description": "Symfony DomCrawler Component",
             "homepage": "https://symfony.com",
-            "time": "2016-12-10 14:24:35"
+            "time": "2016-12-10T14:24:35+00:00"
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@@ -1588,7 +1587,7 @@
             ],
             "description": "Symfony EventDispatcher Component",
             "homepage": "https://symfony.com",
-            "time": "2016-10-13 01:43:15"
+            "time": "2016-10-13T01:43:15+00:00"
         },
         {
             "name": "symfony/http-foundation",
@@ -1643,7 +1642,7 @@
             ],
             "description": "Symfony HttpFoundation Component",
             "homepage": "https://symfony.com",
-            "time": "2016-11-27 04:20:28"
+            "time": "2016-11-27T04:20:28+00:00"
         },
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             "name": "symfony/http-kernel",
@@ -1725,7 +1724,7 @@
             ],
             "description": "Symfony HttpKernel Component",
             "homepage": "https://symfony.com",
-            "time": "2016-12-13 12:16:15"
+            "time": "2016-12-13T12:16:15+00:00"
         },
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             "name": "symfony/polyfill-apcu",
@@ -1778,7 +1777,7 @@
                 "portable",
                 "shim"
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-            "time": "2016-11-14 01:06:16"
+            "time": "2016-11-14T01:06:16+00:00"
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@@ -1837,7 +1836,7 @@
                 "portable",
                 "shim"
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-            "time": "2016-11-14 01:06:16"
+            "time": "2016-11-14T01:06:16+00:00"
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@@ -1896,7 +1895,7 @@
                 "portable",
                 "shim"
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-            "time": "2016-11-14 01:06:16"
+            "time": "2016-11-14T01:06:16+00:00"
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         {
             "name": "symfony/polyfill-php54",
@@ -1954,7 +1953,7 @@
                 "portable",
                 "shim"
             ],
-            "time": "2016-11-14 01:06:16"
+            "time": "2016-11-14T01:06:16+00:00"
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             "name": "symfony/polyfill-php55",
@@ -2010,7 +2009,7 @@
                 "portable",
                 "shim"
             ],
-            "time": "2016-11-14 01:06:16"
+            "time": "2016-11-14T01:06:16+00:00"
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@@ -2059,7 +2058,7 @@
             ],
             "description": "Symfony Process Component",
             "homepage": "https://symfony.com",
-            "time": "2016-11-24 00:43:03"
+            "time": "2016-11-24T00:43:03+00:00"
         },
         {
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@@ -2113,7 +2112,7 @@
                 "http-message",
                 "psr-7"
             ],
-            "time": "2015-05-29 17:57:12"
+            "time": "2015-05-29T17:57:12+00:00"
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         {
             "name": "symfony/routing",
@@ -2188,7 +2187,7 @@
                 "uri",
                 "url"
             ],
-            "time": "2016-11-25 12:26:42"
+            "time": "2016-11-25T12:26:42+00:00"
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         {
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@@ -2252,7 +2251,7 @@
             ],
             "description": "Symfony Serializer Component",
             "homepage": "https://symfony.com",
-            "time": "2016-11-03 07:52:58"
+            "time": "2016-11-03T07:52:58+00:00"
         },
         {
             "name": "symfony/translation",
@@ -2316,7 +2315,7 @@
             ],
             "description": "Symfony Translation Component",
             "homepage": "https://symfony.com",
-            "time": "2016-11-18 21:10:01"
+            "time": "2016-11-18T21:10:01+00:00"
         },
         {
             "name": "symfony/validator",
@@ -2389,7 +2388,7 @@
             ],
             "description": "Symfony Validator Component",
             "homepage": "https://symfony.com",
-            "time": "2016-12-08 15:59:39"
+            "time": "2016-12-08T15:59:39+00:00"
         },
         {
             "name": "symfony/yaml",
@@ -2438,33 +2437,34 @@
             ],
             "description": "Symfony Yaml Component",
             "homepage": "https://symfony.com",
-            "time": "2016-11-14 16:15:57"
+            "time": "2016-11-14T16:15:57+00:00"
         },
         {
             "name": "twig/twig",
-            "version": "v1.25.0",
+            "version": "v2.0.0",
             "source": {
                 "type": "git",
                 "url": "https://github.com/twigphp/Twig.git",
-                "reference": "f16a634ab08d87e520da5671ec52153d627f10f6"
+                "reference": "2a86dde1288d7270169083d0e078dc7ebe0f48b6"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/twigphp/Twig/zipball/f16a634ab08d87e520da5671ec52153d627f10f6",
-                "reference": "f16a634ab08d87e520da5671ec52153d627f10f6",
+                "url": "https://api.github.com/repos/twigphp/Twig/zipball/2a86dde1288d7270169083d0e078dc7ebe0f48b6",
+                "reference": "2a86dde1288d7270169083d0e078dc7ebe0f48b6",
                 "shasum": ""
             },
             "require": {
-                "php": ">=5.2.7"
+                "php": "^7.0",
+                "symfony/polyfill-mbstring": "~1.0"
             },
             "require-dev": {
                 "symfony/debug": "~2.7",
-                "symfony/phpunit-bridge": "~2.7"
+                "symfony/phpunit-bridge": "~3.2"
             },
             "type": "library",
             "extra": {
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+                    "dev-master": "2.0-dev"
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             "autoload": {
@@ -2499,7 +2499,7 @@
             "keywords": [
                 "templating"
             ],
-            "time": "2016-09-21 23:05:12"
+            "time": "2017-01-05T17:12:02+00:00"
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             "name": "wikimedia/composer-merge-plugin",
@@ -2548,7 +2548,7 @@
                 }
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             "description": "Composer plugin to merge multiple composer.json files",
-            "time": "2016-03-08 17:11:37"
+            "time": "2016-03-08T17:11:37+00:00"
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         {
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@@ -2598,7 +2598,7 @@
                 "psr",
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             ],
-            "time": "2015-08-10 20:04:20"
+            "time": "2015-08-10T20:04:20+00:00"
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         {
             "name": "zendframework/zend-escaper",
@@ -2642,7 +2642,7 @@
                 "escaper",
                 "zf2"
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-            "time": "2015-06-03 14:05:37"
+            "time": "2015-06-03T14:05:37+00:00"
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         {
             "name": "zendframework/zend-feed",
@@ -2701,7 +2701,7 @@
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-            "time": "2015-08-04 21:39:18"
+            "time": "2015-08-04T21:39:18+00:00"
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             "name": "zendframework/zend-hydrator",
@@ -2757,7 +2757,7 @@
                 "hydrator",
                 "zf2"
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-            "time": "2015-09-17 14:06:43"
+            "time": "2015-09-17T14:06:43+00:00"
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             "name": "zendframework/zend-stdlib",
@@ -2815,7 +2815,7 @@
                 "stdlib",
                 "zf2"
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-            "time": "2015-09-25 04:06:33"
+            "time": "2015-09-25T04:06:33+00:00"
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     "packages-dev": [
@@ -2875,7 +2875,7 @@
                 "testing",
                 "web"
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-            "time": "2016-10-17 08:31:38"
+            "time": "2016-10-17T08:31:38+00:00"
         },
         {
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@@ -2931,7 +2931,7 @@
                 "browser",
                 "testing"
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-            "time": "2016-03-05 08:59:47"
+            "time": "2016-03-05T08:59:47+00:00"
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         {
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@@ -2986,7 +2986,7 @@
                 "headless",
                 "testing"
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-            "time": "2016-03-05 09:04:22"
+            "time": "2016-03-05T09:04:22+00:00"
         },
         {
             "name": "doctrine/instantiator",
@@ -3040,7 +3040,7 @@
                 "constructor",
                 "instantiate"
             ],
-            "time": "2015-06-14 21:17:01"
+            "time": "2015-06-14T21:17:01+00:00"
         },
         {
             "name": "fabpot/goutte",
@@ -3089,7 +3089,7 @@
             "keywords": [
                 "scraper"
             ],
-            "time": "2015-11-05 12:58:44"
+            "time": "2015-11-05T12:58:44+00:00"
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@@ -3146,7 +3146,7 @@
                 "headless",
                 "phantomjs"
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-            "time": "2016-01-18 09:21:03"
+            "time": "2016-01-18T09:21:03+00:00"
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         {
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@@ -3207,7 +3207,7 @@
                 "phantomjs",
                 "testing"
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-            "time": "2015-12-04 13:55:02"
+            "time": "2015-12-04T13:55:02+00:00"
         },
         {
             "name": "mikey179/vfsStream",
@@ -3253,7 +3253,7 @@
             ],
             "description": "Virtual file system to mock the real file system in unit tests.",
             "homepage": "http://vfs.bovigo.org/",
-            "time": "2015-10-06 16:59:57"
+            "time": "2015-10-06T16:59:57+00:00"
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         {
             "name": "phpdocumentor/reflection-docblock",
@@ -3302,7 +3302,7 @@
                     "email": "mike.vanriel@naenius.com"
                 }
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-            "time": "2015-02-03 12:10:50"
+            "time": "2015-02-03T12:10:50+00:00"
         },
         {
             "name": "phpspec/prophecy",
@@ -3362,7 +3362,7 @@
                 "spy",
                 "stub"
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-            "time": "2015-08-13 10:07:40"
+            "time": "2015-08-13T10:07:40+00:00"
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         {
             "name": "phpunit/php-code-coverage",
@@ -3424,7 +3424,7 @@
                 "testing",
                 "xunit"
             ],
-            "time": "2015-10-06 15:47:00"
+            "time": "2015-10-06T15:47:00+00:00"
         },
         {
             "name": "phpunit/php-file-iterator",
@@ -3471,7 +3471,7 @@
                 "filesystem",
                 "iterator"
             ],
-            "time": "2015-06-21 13:08:43"
+            "time": "2015-06-21T13:08:43+00:00"
         },
         {
             "name": "phpunit/php-text-template",
@@ -3512,7 +3512,7 @@
             "keywords": [
                 "template"
             ],
-            "time": "2015-06-21 13:50:34"
+            "time": "2015-06-21T13:50:34+00:00"
         },
         {
             "name": "phpunit/php-timer",
@@ -3553,7 +3553,7 @@
             "keywords": [
                 "timer"
             ],
-            "time": "2015-06-21 08:01:12"
+            "time": "2015-06-21T08:01:12+00:00"
         },
         {
             "name": "phpunit/php-token-stream",
@@ -3602,7 +3602,7 @@
             "keywords": [
                 "tokenizer"
             ],
-            "time": "2015-09-15 10:49:45"
+            "time": "2015-09-15T10:49:45+00:00"
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         {
             "name": "phpunit/phpunit",
@@ -3674,7 +3674,7 @@
                 "testing",
                 "xunit"
             ],
-            "time": "2016-07-21 06:48:14"
+            "time": "2016-07-21T06:48:14+00:00"
         },
         {
             "name": "phpunit/phpunit-mock-objects",
@@ -3730,7 +3730,7 @@
                 "mock",
                 "xunit"
             ],
-            "time": "2015-10-02 06:51:40"
+            "time": "2015-10-02T06:51:40+00:00"
         },
         {
             "name": "sebastian/comparator",
@@ -3794,7 +3794,7 @@
                 "compare",
                 "equality"
             ],
-            "time": "2015-07-26 15:48:44"
+            "time": "2015-07-26T15:48:44+00:00"
         },
         {
             "name": "sebastian/diff",
@@ -3846,7 +3846,7 @@
             "keywords": [
                 "diff"
             ],
-            "time": "2015-02-22 15:13:53"
+            "time": "2015-02-22T15:13:53+00:00"
         },
         {
             "name": "sebastian/environment",
@@ -3896,7 +3896,7 @@
                 "environment",
                 "hhvm"
             ],
-            "time": "2015-08-03 06:14:51"
+            "time": "2015-08-03T06:14:51+00:00"
         },
         {
             "name": "sebastian/exporter",
@@ -3962,7 +3962,7 @@
                 "export",
                 "exporter"
             ],
-            "time": "2015-06-21 07:55:53"
+            "time": "2015-06-21T07:55:53+00:00"
         },
         {
             "name": "sebastian/global-state",
@@ -4013,7 +4013,7 @@
             "keywords": [
                 "global state"
             ],
-            "time": "2014-10-06 09:23:50"
+            "time": "2014-10-06T09:23:50+00:00"
         },
         {
             "name": "sebastian/recursion-context",
@@ -4066,7 +4066,7 @@
             ],
             "description": "Provides functionality to recursively process PHP variables",
             "homepage": "http://www.github.com/sebastianbergmann/recursion-context",
-            "time": "2015-06-21 08:04:50"
+            "time": "2015-06-21T08:04:50+00:00"
         },
         {
             "name": "sebastian/version",
@@ -4101,7 +4101,7 @@
             ],
             "description": "Library that helps with managing the version number of Git-hosted PHP projects",
             "homepage": "https://github.com/sebastianbergmann/version",
-            "time": "2015-06-21 13:59:46"
+            "time": "2015-06-21T13:59:46+00:00"
         },
         {
             "name": "symfony/browser-kit",
@@ -4158,7 +4158,7 @@
             ],
             "description": "Symfony BrowserKit Component",
             "homepage": "https://symfony.com",
-            "time": "2016-10-13 13:35:11"
+            "time": "2016-10-13T13:35:11+00:00"
         },
         {
             "name": "symfony/css-selector",
@@ -4211,7 +4211,7 @@
             ],
             "description": "Symfony CssSelector Component",
             "homepage": "https://symfony.com",
-            "time": "2016-11-03 07:52:58"
+            "time": "2016-11-03T07:52:58+00:00"
         }
     ],
     "aliases": [],
diff --git a/core/composer.json b/core/composer.json
index 71f07d029f..78e94c7b01 100644
--- a/core/composer.json
+++ b/core/composer.json
@@ -19,7 +19,7 @@
         "symfony/process": "~2.8",
         "symfony/polyfill-iconv": "~1.0",
         "symfony/yaml": "~2.8",
-        "twig/twig": "^1.23.1",
+        "twig/twig": "^1.23.1|^2",
         "doctrine/common": "2.5.*",
         "doctrine/annotations": "1.2.*",
         "guzzlehttp/guzzle": "^6.2.1",
diff --git a/core/lib/Drupal/Core/Template/Loader/StringLoader.php b/core/lib/Drupal/Core/Template/Loader/StringLoader.php
index 6325b9e98a..400bab578b 100644
--- a/core/lib/Drupal/Core/Template/Loader/StringLoader.php
+++ b/core/lib/Drupal/Core/Template/Loader/StringLoader.php
@@ -20,7 +20,7 @@
  * @see \Drupal\Core\Render\Element\InlineTemplate
  * @see twig_render_template()
  */
-class StringLoader implements \Twig_LoaderInterface, \Twig_ExistsLoaderInterface {
+class StringLoader implements \Twig_LoaderInterface, \Twig_ExistsLoaderInterface, \Twig_SourceContextLoaderInterface {
 
   /**
    * {@inheritdoc}
@@ -44,6 +44,14 @@ public function getSource($name) {
   /**
    * {@inheritdoc}
    */
+  public function getSourceContext($name) {
+    $name = (string) $name;
+    return new \Twig_Source($name, $name);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
   public function getCacheKey($name) {
     return $name;
   }
diff --git a/core/lib/Drupal/Core/Template/TwigEnvironment.php b/core/lib/Drupal/Core/Template/TwigEnvironment.php
index f5ee459767..dc44520f2d 100644
--- a/core/lib/Drupal/Core/Template/TwigEnvironment.php
+++ b/core/lib/Drupal/Core/Template/TwigEnvironment.php
@@ -24,6 +24,8 @@ class TwigEnvironment extends \Twig_Environment {
   protected $templateClasses;
 
   protected $twigCachePrefix = '';
+  
+  protected $templateClassPrefix = '__TwigTemplate_';
 
   /**
    * Constructs a TwigEnvironment object and stores cache and storage
@@ -42,11 +44,7 @@ class TwigEnvironment extends \Twig_Environment {
    * @param array $options
    *   The options for the Twig environment.
    */
-  public function __construct($root, CacheBackendInterface $cache, $twig_extension_hash, StateInterface $state, \Twig_LoaderInterface $loader = NULL, $options = array()) {
-    // Ensure that twig.engine is loaded, given that it is needed to render a
-    // template because functions like TwigExtension::escapeFilter() are called.
-    require_once $root . '/core/themes/engines/twig/twig.engine';
-
+  public function __construct($root, CacheBackendInterface $cache, $twig_extension_hash, StateInterface $state, \Twig_LoaderInterface $loader = NULL, array $options = array()) {
     $this->templateClasses = array();
 
     $options += array(
@@ -57,11 +55,6 @@ public function __construct($root, CacheBackendInterface $cache, $twig_extension
     );
     // Ensure autoescaping is always on.
     $options['autoescape'] = 'html';
-
-    $policy = new TwigSandboxPolicy();
-    $sandbox = new \Twig_Extension_Sandbox($policy, TRUE);
-    $this->addExtension($sandbox);
-
     if ($options['cache'] === TRUE) {
       $current = $state->get('twig_extension_hash_prefix', ['twig_extension_hash' => '']);
       if ($current['twig_extension_hash'] !== $twig_extension_hash || empty($current['twig_cache_prefix'])) {
@@ -78,8 +71,11 @@ public function __construct($root, CacheBackendInterface $cache, $twig_extension
       $options['cache'] = new TwigPhpStorageCache($cache, $this->twigCachePrefix);
     }
 
-    $this->loader = $loader;
-    parent::__construct($this->loader, $options);
+    $this->setLoader($loader);
+    parent::__construct($this->getLoader(), $options);
+    $policy = new TwigSandboxPolicy();
+    $sandbox = new \Twig_Extension_Sandbox($policy, TRUE);
+    $this->addExtension($sandbox);
   }
 
   /**
@@ -110,7 +106,7 @@ public function getTemplateClass($name, $index = NULL) {
     // node.html.twig for the output of each node and the same compiled class.
     $cache_index = $name . (NULL === $index ? '' : '_' . $index);
     if (!isset($this->templateClasses[$cache_index])) {
-      $this->templateClasses[$cache_index] = $this->templateClassPrefix . hash('sha256', $this->loader->getCacheKey($name)) . (NULL === $index ? '' : '_' . $index);
+      $this->templateClasses[$cache_index] = $this->templateClassPrefix . hash('sha256', $this->getLoader()->getCacheKey($name)) . (NULL === $index ? '' : '_' . $index);
     }
     return $this->templateClasses[$cache_index];
   }
diff --git a/core/lib/Drupal/Core/Template/TwigExtension.php b/core/lib/Drupal/Core/Template/TwigExtension.php
index 7d67ff991c..b3edd81867 100644
--- a/core/lib/Drupal/Core/Template/TwigExtension.php
+++ b/core/lib/Drupal/Core/Template/TwigExtension.php
@@ -177,7 +177,7 @@ public function getFilters() {
       new \Twig_SimpleFilter('safe_join', [$this, 'safeJoin'], ['needs_environment' => TRUE, 'is_safe' => ['html']]),
 
       // Array filters.
-      new \Twig_SimpleFilter('without', 'twig_without'),
+      new \Twig_SimpleFilter('without', [$this, 'withoutFilter']),
 
       // CSS class and ID filters.
       new \Twig_SimpleFilter('clean_class', '\Drupal\Component\Utility\Html::getClass'),
@@ -629,4 +629,37 @@ public function createAttribute(array $attributes = []) {
     return new Attribute($attributes);
   }
 
+  /**
+   * Removes child elements from a copy of the original array.
+   *
+   * Creates a copy of the renderable array and removes child elements by key
+   * specified through filter's arguments. The copy can be printed without these
+   * elements. The original renderable array is still available and can be used
+   * to print child elements in their entirety in the twig template.
+   *
+   * @param array|object $element
+   *   The parent renderable array to exclude the child items.
+   * @param string[] $args, ...
+   *   The string keys of $element to prevent printing.
+   *
+   * @return array
+   *   The filtered renderable array.
+   */
+  public function withoutFilter($element) {
+    if ($element instanceof \ArrayAccess) {
+      $filtered_element = clone $element;
+    }
+    else {
+      $filtered_element = $element;
+    }
+    $args = func_get_args();
+    unset($args[0]);
+    foreach ($args as $arg) {
+      if (isset($filtered_element[$arg])) {
+        unset($filtered_element[$arg]);
+      }
+    }
+    return $filtered_element;
+  }
+
 }
diff --git a/core/lib/Drupal/Core/Template/TwigNodeTrans.php b/core/lib/Drupal/Core/Template/TwigNodeTrans.php
index 21006fd1ed..1caf3b4e4b 100644
--- a/core/lib/Drupal/Core/Template/TwigNodeTrans.php
+++ b/core/lib/Drupal/Core/Template/TwigNodeTrans.php
@@ -17,7 +17,7 @@ class TwigNodeTrans extends \Twig_Node {
   /**
    * {@inheritdoc}
    */
-  public function __construct(\Twig_Node $body, \Twig_Node $plural = NULL, \Twig_Node_Expression $count = NULL, \Twig_Node_Expression $options = NULL, $lineno, $tag = NULL) {
+  public function __construct(\Twig_Node $body, \Twig_Node $plural, \Twig_Node $count, \Twig_Node $options, $lineno, $tag = NULL) {
     parent::__construct(array(
       'count' => $count,
       'body' => $body,
@@ -103,7 +103,7 @@ protected function compileString(\Twig_Node $body) {
       $text = '';
 
       foreach ($body as $node) {
-        if (get_class($node) === 'Twig_Node' && $node->getNode(0) instanceof \Twig_Node_SetTemp) {
+        if (get_class($node) === 'Twig_Node') {
           $node = $node->getNode(1);
         }
 
@@ -157,7 +157,7 @@ protected function compileString(\Twig_Node $body) {
             if (!is_null($args)) {
               $argName = $args->getAttribute('name');
             }
-            $expr = new \Twig_Node_Expression_Name($argName, $n->getLine());
+            $expr = new \Twig_Node_Expression_Name($argName, $n->getTemplateLine());
           }
           $placeholder = sprintf('%s%s', $argPrefix, $argName);
           $text .= $placeholder;
@@ -176,7 +176,7 @@ protected function compileString(\Twig_Node $body) {
       $text = $body->getAttribute('data');
     }
 
-    return array(new \Twig_Node(array(new \Twig_Node_Expression_Constant(trim($text), $body->getLine()))), $tokens);
+    return array(new \Twig_Node(array(new \Twig_Node_Expression_Constant(trim($text), $body->getTemplateLine()))), $tokens);
   }
 
 }
diff --git a/core/lib/Drupal/Core/Template/TwigNodeVisitor.php b/core/lib/Drupal/Core/Template/TwigNodeVisitor.php
index 6222d69e3a..17cbb428cb 100644
--- a/core/lib/Drupal/Core/Template/TwigNodeVisitor.php
+++ b/core/lib/Drupal/Core/Template/TwigNodeVisitor.php
@@ -33,7 +33,7 @@ protected function doLeaveNode(\Twig_Node $node, \Twig_Environment $env) {
         return $node;
       }
       $class = get_class($node);
-      $line = $node->getLine();
+      $line = $node->getTemplateLine();
       return new $class(
         new \Twig_Node_Expression_Function('render_var', new \Twig_Node(array($node->getNode('expr'))), $line),
         $line
diff --git a/core/lib/Drupal/Core/Template/TwigTransTokenParser.php b/core/lib/Drupal/Core/Template/TwigTransTokenParser.php
index fb16017537..579f2d4331 100644
--- a/core/lib/Drupal/Core/Template/TwigTransTokenParser.php
+++ b/core/lib/Drupal/Core/Template/TwigTransTokenParser.php
@@ -21,10 +21,10 @@ class TwigTransTokenParser extends \Twig_TokenParser {
   public function parse(\Twig_Token $token) {
     $lineno = $token->getLine();
     $stream = $this->parser->getStream();
-    $body = NULL;
-    $options = NULL;
-    $count = NULL;
-    $plural = NULL;
+    $body = [];
+    $options = [];
+    $count = [];
+    $plural = [];
 
     if (!$stream->test(\Twig_Token::BLOCK_END_TYPE) && $stream->test(\Twig_Token::STRING_TYPE)) {
       $body = $this->parser->getExpressionParser()->parseExpression();
@@ -47,6 +47,18 @@ public function parse(\Twig_Token $token) {
 
     $this->checkTransString($body, $lineno);
 
+    if ($body === []) {
+      $body = new \Twig_Node($body);
+    }
+    if ($plural === []) {
+      $plural = new \Twig_Node($plural);
+    }
+    if ($count === []) {
+      $count = new \Twig_Node($count);
+    }
+    if ($options === []) {
+      $options = new \Twig_Node($options);
+    }
     $node = new TwigNodeTrans($body, $plural, $count, $options, $lineno, $this->getTag());
 
     return $node;
diff --git a/core/modules/system/tests/modules/twig_extension_test/src/TwigExtension/TestExtension.php b/core/modules/system/tests/modules/twig_extension_test/src/TwigExtension/TestExtension.php
index 78d1020288..3baa6e2b9c 100644
--- a/core/modules/system/tests/modules/twig_extension_test/src/TwigExtension/TestExtension.php
+++ b/core/modules/system/tests/modules/twig_extension_test/src/TwigExtension/TestExtension.php
@@ -2,11 +2,10 @@
 
 namespace Drupal\twig_extension_test\TwigExtension;
 
-
 /**
  * A test Twig extension that adds a custom function and a custom filter.
  */
-class TestExtension extends \Twig_Extension {
+class TestExtension extends \TwigExtension {
 
   /**
    * Generates a list of all Twig functions that this extension defines.
@@ -21,9 +20,9 @@ class TestExtension extends \Twig_Extension {
    *   The value is a standard PHP callback that defines what the function does.
    */
   public function getFunctions() {
-    return array(
-      'testfunc' => new \Twig_Function_Function(array('Drupal\twig_extension_test\TwigExtension\TestExtension', 'testFunction')),
-    );
+    return [
+      new \Twig_SimpleFunction('testfunc', [$this, 'testFunction']),
+    ];
   }
 
   /**
@@ -39,9 +38,9 @@ public function getFunctions() {
    *   The value is a standard PHP callback that defines what the filter does.
    */
   public function getFilters() {
-    return array(
-      'testfilter' => new \Twig_Filter_Function(array('Drupal\twig_extension_test\TwigExtension\TestExtension', 'testFilter')),
-    );
+    return [
+      new \Twig_SimpleFilter('testfilter', [$this, 'testFilter']),
+    ];
   }
 
   /**
diff --git a/core/modules/system/tests/modules/twig_extension_test/twig_extension_test.services.yml b/core/modules/system/tests/modules/twig_extension_test/twig_extension_test.services.yml
index 491d1e8c5b..8784c0f341 100644
--- a/core/modules/system/tests/modules/twig_extension_test/twig_extension_test.services.yml
+++ b/core/modules/system/tests/modules/twig_extension_test/twig_extension_test.services.yml
@@ -1,6 +1,5 @@
 services:
   twig_extension_test.twig.test_extension:
-    arguments: ['@renderer']
     class: Drupal\twig_extension_test\TwigExtension\TestExtension
     tags:
       - { name: twig.extension }
diff --git a/core/tests/Drupal/KernelTests/Core/Theme/TwigEnvironmentTest.php b/core/tests/Drupal/KernelTests/Core/Theme/TwigEnvironmentTest.php
index c3e7af6a3c..3804e1072c 100644
--- a/core/tests/Drupal/KernelTests/Core/Theme/TwigEnvironmentTest.php
+++ b/core/tests/Drupal/KernelTests/Core/Theme/TwigEnvironmentTest.php
@@ -115,13 +115,18 @@ public function testCacheFilename() {
     // Note: Later we refetch the twig service in order to bypass its internal
     // static cache.
     $environment = \Drupal::service('twig');
+    $template_path = 'core/modules/system/templates/container.html.twig';
 
-    $original_filename = $environment->getCacheFilename('core/modules/system/templates/container.html.twig');
+    $cache = $environment->getCache();
+    $class = $environment->getTemplateClass($template_path);
+    $original_filename = $cache->generateKey($template_path, $class);
     \Drupal::getContainer()->set('twig', NULL);
 
     \Drupal::service('module_installer')->install(['twig_extension_test']);
     $environment = \Drupal::service('twig');
-    $new_extension_filename = $environment->getCacheFilename('core/modules/system/templates/container.html.twig');
+    $cache = $environment->getCache();
+    $class = $environment->getTemplateClass($template_path);
+    $new_extension_filename = $cache->generateKey($template_path, $class);
     \Drupal::getContainer()->set('twig', NULL);
 
     $this->assertNotEqual($new_extension_filename, $original_filename);
diff --git a/core/tests/Drupal/Tests/Core/Template/AttributeTest.php b/core/tests/Drupal/Tests/Core/Template/AttributeTest.php
index 09ec9894dc..3ffd46da3b 100644
--- a/core/tests/Drupal/Tests/Core/Template/AttributeTest.php
+++ b/core/tests/Drupal/Tests/Core/Template/AttributeTest.php
@@ -263,7 +263,7 @@ public function testChainAddRemoveClasses() {
    * @covers ::addClass
    */
   public function testTwigAddRemoveClasses($template, $expected, $seed_attributes = array()) {
-    $loader = new \Twig_Loader_String();
+    $loader = new \Twig_Loader_Array($template);
     $twig = new \Twig_Environment($loader);
     $data = array('attributes' => new Attribute($seed_attributes));
     $result = $twig->render($template, $data);
diff --git a/core/tests/Drupal/Tests/Core/Template/TwigExtensionTest.php b/core/tests/Drupal/Tests/Core/Template/TwigExtensionTest.php
index 396b2f9765..eb8cfb34b6 100644
--- a/core/tests/Drupal/Tests/Core/Template/TwigExtensionTest.php
+++ b/core/tests/Drupal/Tests/Core/Template/TwigExtensionTest.php
@@ -10,6 +10,19 @@
 use Drupal\Core\Template\TwigExtension;
 use Drupal\Tests\UnitTestCase;
 
+if (!function_exists(__NAMESPACE__ . 't')) {
+
+  function t($string, array $args = []) {
+    return strtr($string, $args);
+  }
+
+}
+if (!function_exists(__NAMESPACE__ . 'file_create_url')) {
+
+  function file_create_url() {}
+
+}
+
 /**
  * Tests the twig extension.
  *
@@ -74,7 +87,9 @@ public function setUp() {
    * @dataProvider providerTestEscaping
    */
   public function testEscaping($template, $expected) {
-    $twig = new \Twig_Environment(NULL, array(
+    $renderer = $this->getMock('\Drupal\Core\Render\RendererInterface');
+    $loader = new \Twig_Loader_Filesystem();
+    $twig = new \Twig_Environment($loader, array(
       'debug' => TRUE,
       'cache' => FALSE,
       'autoescape' => 'html',
@@ -134,7 +149,7 @@ public function testActiveTheme() {
       ->method('getActiveTheme')
       ->willReturn($active_theme);
 
-    $loader = new \Twig_Loader_String();
+    $loader = new \Twig_Loader_Array([]);
     $twig = new \Twig_Environment($loader);
     $twig->addExtension($this->systemUnderTest);
     $result = $twig->render('{{ active_theme() }}');
@@ -171,7 +186,7 @@ public function testActiveThemePath() {
       ->method('getActiveTheme')
       ->willReturn($active_theme);
 
-    $loader = new \Twig_Loader_String();
+    $loader = new \Twig_Loader_Array([]);
     $twig = new \Twig_Environment($loader);
     $twig->addExtension($this->systemUnderTest);
     $result = $twig->render('{{ active_theme_path() }}');
@@ -184,7 +199,9 @@ public function testActiveThemePath() {
    * @covers ::escapeFilter
    */
   public function testSafeStringEscaping() {
-    $twig = new \Twig_Environment(NULL, array(
+    $renderer = $this->getMock('\Drupal\Core\Render\RendererInterface');
+    $loader = new \Twig_Loader_Filesystem();
+    $twig = new \Twig_Environment($loader, array(
       'debug' => TRUE,
       'cache' => FALSE,
       'autoescape' => 'html',
@@ -268,7 +285,8 @@ public function providerTestRenderVar() {
    * @covers ::bubbleArgMetadata
    */
   public function testEscapeWithGeneratedLink() {
-    $twig = new \Twig_Environment(NULL, [
+    $loader = new \Twig_Loader_Filesystem();
+    $twig = new \Twig_Environment($loader, [
         'debug' => TRUE,
         'cache' => FALSE,
         'autoescape' => 'html',
@@ -326,7 +344,7 @@ public function testRenderVarWithGeneratedLink() {
    * @covers ::createAttribute
    */
   public function testCreateAttribute() {
-    $loader = new StringLoader();
+    $loader = new \Twig_Loader_Array([]);
     $twig = new \Twig_Environment($loader);
     $twig->addExtension($this->systemUnderTest);