MB-10960:  add Debian-7 builders to status dashboards

Change-Id: I71274703b6b468a14d71b749f55b4b59fd208c5e
Reviewed-on: http://review.couchbase.org/40065
Reviewed-by: Philip Labee <philip@couchbase.com>
Tested-by: Philip Labee <philip@couchbase.com>