Merge branch 'stable-3.0' into stable-3.1

* stable-3.0:
  Introduce a configuration to define time lapse for rate limiter
  Upgrade bazlets to latest stable-3.0 to build with 3.0.15 API
  Upgrade bazlets to latest stable-2.16 to build with 2.16.26 API
  Upgrade bazlets to latest stable-2.16 to build with 2.16.23 API

Conflict resolution for WORKSPACE is to keep the original bazlets
version. Also, adjust the test to use project.nameKeys instead of new
Project.NameKeys.

Change-Id: Ic5af1ac3006d66884ed5d257bacee8a5f26a3b69