Merge branch 'stable-3.0' into stable-3.1

* stable-3.0:
  Upgrade bazlets to latest stable-3.0 to build with 3.0.9 API
  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: Ie55fb76eb8e1681ad915cf868baa5b711a384445