On master branch, tag tarballs as dev snapshots

Change-Id: Ia0bdad7fdff2a8d0d27b1e703ff20a2a89a102cc
Use correct stack_id arg name for metadata_update()

Change-Id: I5e4554aa7670d505f45b1512b7135276079b3918
Merge "Use correct stack_id arg name for metadata_update()"
Merge "On master branch, tag tarballs as dev snapshots"