Merge branch 'stable-2.15' into stable-2.16 * stable-2.15: Upgrade bazlets to latest stable-2.15 to build with 2.15.18 API Bazel: Migrate workspace status script to python Upgrade bazlets to latest stable-2.15 Upgrade bazlets to latest stable-2.14 Change-Id: Ibffa8691709b093b1ddc26666c596c61c8baa2db