CBQE-0: fix upgrade- get correct version fo upgrade

Change-Id: I58a9be033245bce51510146fe4759ad2926a9296
Reviewed-on: http://review.couchbase.org/27914
Tested-by: buildbot <build@couchbase.com>
Reviewed-by: Andrei Baranouski <andrei.baranouski@gmail.com>