Merge branch 'stable-2.12'

* stable-2.12:
  Build with plugin API 2.12 final release

Change-Id: I94cf6af14f3d6f0d9102dc0f9976be620f193a9e
tree: 63d28bd5f4e77188800e0a7160cfef43a002ecb9
  1. lib/
  2. src/
  3. .buckconfig
  4. .gitignore
  5. BUCK
  6. LICENSE