entity_reference_revisions 8.x-1.0-rc7

A next step towards a stable release.

Most important additions: A diff plugin, a fix to make Search API integration work, and many bugfixes.

Changes since 8.x-1.0-rc6:

• #2711429 by tduong, Berdir: Test ERR default values and configuration dependencies
• #2721531 by yongt9412: Fix label on property definitions of Entity reference revisions field type
• #2433099 by LKS90, yongt9412, sasanikolic, Anushka-mp, edurenye, miro_dietiker: Provide a custom diff plugin
• #2433099 by yongt9412: Provide a custom diff plugin - test dependency
• #2690007 by tduong, sskt: Remove drupal_render deprecated method and refactor non-functional cleanups
• #2709241 by tduong: Drop @file path documentation according to standard coding
• #2598138 by larowlan, zach.bimson, webflo: HAL serialization for ERRItem is broken
• #2706883 by yongt9412, Berdir: Fatal error when call to getRevisionId()