CBQE-0 add return false for unknown edition

Change-Id: Ia815750b221d4b2d89fdac6bb010430c7c216971
Reviewed-on: http://review.couchbase.org/35418
Tested-by: Thuan Nguyen <soccon@gmail.com>
Reviewed-by: Ketaki Gangal <ketakigangal@gmail.com>