Stomp-py

* Fix problem with heartbeat listener (https://github.com/jasonrbriggs/stomp.py/issues/4)
* Add alternate aliases for the connection classes
* Add initial Version multicast adapter (providing an interface to use the stomp.py API and send messages via multicast)
- note: work in progress

* Fix missing headers in connect func
* Throw ConnectFailedException when a connection fails in the 1.2 protocol - if wait=True is set

* Add command-line subscription listener. So you can do:
> stomp -H localhost -P 61613 -L /queue/test
* Add verbose option to command-line client (verbose "on" by default, if "off", headers aren't written to stdout)
* Fix problem with connect wait (should not wait if the connection fails)
* Throw exception when the connect fails (only if wait=True)
* Add PrintingListener (useful for debugging)

* Fix ack/nack function inconsistencies in each protocol Version (as per https://github.com/jasonrbriggs/stomp.py/issues/1)

* Add script for cmd line access (so you can run `stomp -H localhost -P 61613` rather than python $PATH_TO_STOMP/stomp ....)

* Fix minor error with 1.2 connections. Add basic unit tests for 1.0, and 1.2