Cleanup test_multiple_set_delete_with_metas_full_eviction
Cleanup test_multiple_set_delete_with_metas_full_eviction

* Use std::thread instead of old style threads
* Use CAS = 0 and make sure all operations succeed
  (and check that the counters gets updated correctly)

Change-Id: Ieed1018af965108f5a39286ffef767940f7899a4
Reviewed-on: http://review.couchbase.org/101644
Tested-by: Build Bot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>
Reviewed-by: Dave Rigby <a09264da4832c7ff1d3bf1608a19f4b870f93750@couchbase.com>

daverigby/kv_engine,daverigby/kv_engine,daverigby/kv_engine,daverigby/kv_engine