Update bazlets to latest revision on master

This fixes a build failure [1] with the latest bazel caused by
deprecation of the set() constructor.

Also, switch to consuming gerrit API from local maven so that
the 2.16-SNAPSHOT version is used.

[1] http://paste.openstack.org/show/624532/

Change-Id: Iad690244d283ae898098530ad3f68ab463ff27c6