libmemcached is part of moxi

Change-Id: I783326fb75bfe2b1487ef4a94704a77428e9ad8d
Reviewed-on: http://review.couchbase.org/34783
Reviewed-by: Trond Norbye <trond.norbye@gmail.com>
Tested-by: Trond Norbye <trond.norbye@gmail.com>