Revert [#6271] Limit reserved class_key column...
Bump version for real 2.2.7-pl release
xPDO 2.2.7-pl

Merge branch 'release-2.2'

* release-2.2:
  Bump version for real 2.2.7-pl release
  Revert [#6271] Limit reserved class_key column...
xPDO Core 2.2.7-pl

Merge remote-tracking branch 'xpdo/master'

* xpdo/master:
  Bump version for real 2.2.7-pl release
  Revert [#6271] Limit reserved class_key column...