CBQE-0: add 2.2.0 in COUCHBASE_VERSIONS

Change-Id: I0546eb5b30110143fb94e24a62a6126dba08bda6
Reviewed-on: http://review.couchbase.org/27852
Reviewed-by: Andrei Baranouski <andrei.baranouski@gmail.com>
Tested-by: Andrei Baranouski <andrei.baranouski@gmail.com>