relation 7.x-1.0-rc7

The planned release of 7.x-1.0 didn't quite work out. Due to some problems with tests the last blocker issues are not moving forward fast enough. Some important issues have been fixed since last release candidate, like #1649398.

Changes since 7.x-1.0-rc6:

• #2409873 by Dave Reid: Fixed missing foreign key information from relation and relation_revision
• #2193375 by mikran: Administer nodes permission replaced with edit relations permission
• #2349385 by mikran: RelationFeedsProcessor should implement expiryQuery() instead of expire()
• Drupal core version requirement added to relation.info.
• #2397171 by mikran: Disabled relation_migrate tests temporarily to unblock other issues.
• Added a requirement that feeds 7.x-1.0-alpha8 is not compatible with relation_feeds.
• #1649398 by hclaria, mikran, Uhkis: Fixed performance issues by adding separate indexes to endpoints table.
• CONCEPTS.txt and UNINSTALL.txt merged to README.txt, README.txt updated.
• #2352563 by mikran: Fixed unique endpoints Processor setting to work correctly with directionality
• #2347125 by alberto56: Identify generated dummy relations so they can be altered