Merge 'v2.3.1'

* v2.3.1:
  Release notes for 2.3.1
  Release notes for 2.2.2.2
  Fix permissions bug caused by directly inheriting from All-Projects

Conflicts:
	gerrit-server/src/main/java/com/google/gerrit/server/project/SectionSortCache.java

Change-Id: Ic0282b03cd4736fc33558ecca02dd5e34686ea4a