connectable is presently failing during the iptables command:
$ docker logs connectable
2015/08/07 18:28:50 Connectable listening on 10000 ...
Self: 2011f14d0013ed337acf696b3def8737b45eb7d787b4de79e34b1294b8781e9d bridge
2015/08/07 18:28:51 non-zero exit: 1
$ docker logs thirsty_mcclintock
2015/08/07 18:28:51 listen tcp :10000: bind: address already in use