Merge branch 'stable-2.16' into stable-3.0

* stable-2.16:
  Upgrade bazlets to latest stable-2.16 to build with 2.16.19 API
  Align postgresql version used with gerrit core one
  Stop shipping core dependencies within plugin jar
  Sort CONDUCTOR_DEPS and EXECUTOR_DEPS alphabetically

Change-Id: I8f1bcdeb3d53ad32fd0eaf62b6c3a5fb88079ca0