Add foreman_memcache and dalli dependency

dalli (memcache client dep):
http://koji.katello.org/koji/buildinfo?buildID=6301
http://koji.katello.org/koji/buildinfo?buildID=6302
http://koji.katello.org/koji/buildinfo?buildID=6303

foreman_memcache plugin:
http://koji.katello.org/koji/buildinfo?buildID=6304
http://koji.katello.org/koji/buildinfo?buildID=6305
http://koji.katello.org/koji/buildinfo?buildID=6306