MB-100: add vperf config with supposedly high qps rate

Change-Id: I48cf09347a93adebd175b7ddbb82414739d6e011
Reviewed-on: http://review.couchbase.org/27564
Tested-by: buildbot <build@couchbase.com>
Reviewed-by: Pavel Paulau <pavel.paulau@gmail.com>
MB-100: add write test for mrw

Change-Id: Ia9fc672289a971e45c85309b4ea25252c8a4e365
Reviewed-on: http://review.couchbase.org/27577
Reviewed-by: Ronnie Sun <ronnie@couchbase.com>
Tested-by: Ronnie Sun <ronnie@couchbase.com>