composer_manager 8.x-1.0-beta4

Breaking changes:
- 'drush composer-manager-init' has been removed. Use 'php modules/composer/manager/scripts/init.php' (renamed from init.sh)
- core/ is no longer modified. Replace your core folder with the one from the tarball or git, to undo the changes the old composer_manager made to composer.json and vendor. Then follow the new instructions from the README.

Changes since 8.x-1.0-beta3:

• Ensure the correct autoload.php even when composer drupal-update is run instead of composer drupal-update during module init.
• Clean up PackageController.
• #2563385 by fsilva, bojanz: Remove SafeMarkup calls in PackageController
• Clean up JsonFile.
• Document the reasoning behind the config property keys.
• #2555453 by mkalkbrenner: Avoid hash updates in composer.lock
• Detect if a composer install is needed, providing better UX for people not following the README.
• Update PackageManagerTest.
• #2452781 followup: Update PackageManager to read the installed packages from the right vendor dir, special case 'composer/installers'.
• #2452781: Modify /composer.json instead of core/composer.json
• Unit tests should run the parent setUp() method.
• Switch to short array syntax.
• #2551145 by chapabu: Tests are failing with latest dev release
• #2553327: Revamp module initialization