CBLT-164:  if branch doesn't already exist we need to make one

Change-Id: I4783b24191f0fc5b76f9202c2ecfe39587d4bdbd
Reviewed-on: http://review.couchbase.org/32664
Reviewed-by: Philip Labee <philip@couchbase.com>
Tested-by: Philip Labee <philip@couchbase.com>