STOMP 1.2

[igorw]

Introducing 1.2 support should likely have a 1.1 BC layer, since not many brokers support it yet (rabbit 3.0 does).

• Replace the stomp spec in doc dir and README with v1.2
• Support for \r\n
• New heartbeat shizzle

[germansokolov13]

Is 0.2 already production-safe? Or should I go with 0.1 for now?