CBQE-0: exit if ClusterStatus cannot be retrieved

Change-Id: I6709f50a199c27049008d00bceef77bc71480012
Reviewed-on: http://review.couchbase.org/26274
Reviewed-by: Tommie McAfee <tommie@couchbase.com>
Tested-by: Tommie McAfee <tommie@couchbase.com>