CBQE-0: refactor conf/py-181-kv-rebalance-tests.conf

planning to add the sute in jenkins jobs

Change-Id: Ie402f3475dfc1bcbdb46ec495891e65d5104dda9
Reviewed-on: http://review.couchbase.org/34649
Reviewed-by: Andrei Baranouski <andrei.baranouski@gmail.com>
Tested-by: Andrei Baranouski <andrei.baranouski@gmail.com>