MB-28453: memcached_testapp: Add Snappy variant of WITH_META tests
MB-28453: memcached_testapp: Add Snappy variant of WITH_META tests

Expand the testapp with_meta tests to have a Snappy variant. Where
possible this will send complete snappy compressed documents to
the server.

Change-Id: I24fd495c8b3e038618da5d514752e822fa97865d
Reviewed-on: http://review.couchbase.org/90738
Tested-by: Build Bot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>
Reviewed-by: Trond Norbye <60edd2ef23891a753f231b0c6f161dc634079a93@gmail.com>

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