CBQE-680 create specific conf file for windows backup test

Change-Id: Iaa0472e11b51e6f240e7517b433315f78490f5be
Reviewed-on: http://review.couchbase.org/26574
Reviewed-by: Chisheng Hong <chisheng@couchbase.com>
Tested-by: Chisheng Hong <chisheng@couchbase.com>