Enable CTest support on memcached
Enable CTest support on memcached

Include the CTest module in memcached's CMakeList.txt, so the metadata
needed for CTest (and specifically running MemoryChecker tests) is configured.

Note we previously had this configured at the toplevel CMakeLists.txt, however
this only creates the CTest config file (DartConfiguration.tcl) at the
toplevel, where we actually need one at the individual project level.

Change-Id: I1ef019c0e1a067bb5023e358ccefcb42566a5d21
Reviewed-on: http://review.couchbase.org/49313
Reviewed-by: Trond Norbye <60edd2ef23891a753f231b0c6f161dc634079a93@gmail.com>
Tested-by: buildbot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>

daverigby/kv_engine,daverigby/memcached,owendCB/memcached,cloudrain21/memcached-1,daverigby/memcached,cloudrain21/memcached-1,couchbase/memcached,daverigby/memcached,cloudrain21/memcached-1,owendCB/memcached,couchbase/memcached,couchbase/memcached,owendCB/memcached,daverigby/kv_engine,cloudrain21/memcached-1,daverigby/memcached,couchbase/memcached,owendCB/memcached,daverigby/kv_engine,daverigby/kv_engine