Merge branch 'stable-3.1'

* stable-3.1:
  Upgrade bazlets to latest stable-3.1
  Upgrade bazlets to latest stable-3.0
  Upgrade bazlets to latest stable-2.16
  Upgrade bazlets to latest stable-2.15
  Upgrade bazlets to latest stable-2.14

Change-Id: I3a743223fa955bb5639aaab2c7f3de05cb03ee8d