CBQE-2245:: Add tests to check data distribution

Change-Id: I38bd4deb1c10bd7b695d98b339b6513ac505774b
Reviewed-on: http://review.couchbase.org/37022
Tested-by: buildbot <build@couchbase.com>
Reviewed-by: Parag Agarwal <agarwal.parag@gmail.com>
Tested-by: Parag Agarwal <agarwal.parag@gmail.com>