Merge branch 'stable-2.15'

* stable-2.15:
  Upgrade bazlets to latest stable-2.15 to build with 2.15.7 API
  Upgrade bazlets to latest stable-2.14 to build with 2.14.17 API
  Upgrade bazlets to latest stable-2.15 to build with 2.15.6 API
  Upgrade bazlets to latest stable-2.14 to build with 2.14.16 API
  Align Eclipse compiler settings with core Gerrit's
  bazlets: Replace native.git_repository with skylark rule
  Upgrade bazlets to latest stable-2.14 to build with 2.14.15 API

Change-Id: Iee8eec6edfa991202d91fab7cb1c006cea7bff2d