Added check to see that removing with incorrect CAS fails
Added check to see that removing with incorrect CAS fails

Change-Id: I60968654273ea8f2f6faac848ca3323378b529be
Reviewed-on: http://review.couchbase.org/73282
Reviewed-by: David Haikney <429c6ca43f70a1a1104bd68d6b2835bd23bff953@couchbase.com>
Tested-by: Build Bot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>

daverigby/memcached,daverigby/kv_engine,couchbase/memcached,couchbase/memcached,couchbase/memcached,daverigby/kv_engine,daverigby/memcached,daverigby/memcached,daverigby/kv_engine,couchbase/memcached,daverigby/memcached,daverigby/kv_engine