Merge branch 'stable-2.16' into stable-3.0

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

Change-Id: I13cf8ebe5d07747d4a4f0021d097794810b89639
diff --git a/.bazelversion b/.bazelversion
new file mode 100644
index 0000000..09d1d01
--- /dev/null
+++ b/.bazelversion
@@ -0,0 +1,2 @@
+0.29.0
+