Merge branch 'stable-2.16'

* stable-2.16:
  Upgrade bazlets to latest stable-2.16
  Upgrade bazlets to latest stable-2.15
  Upgrade bazlets to latest stable-2.14
  Update bazlets to fix build with bazel 0.23

Change-Id: I407e887747f2f298a39ba73a707cd53eea87f384