Socket.IO implementation

[survivant]

first implementation of Socket.IO for Atmosphere.

Support : Websocket, xhr-polling and json-polling transport.

[buildhive]

Atmosphere Framework » atmosphere #56 UNSTABLE
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[buildhive]

Atmosphere Framework » atmosphere #57 UNSTABLE
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[jfarcand]

OK, integrated. I did a major refactoring and will continue working on it. Note:

** Chat tests have been deleted. Re-add them once you have them working embedded
** SocketIOAtmosphereHandler is now an abstract class, hidding the AtmosphereHandler#xxx method (marked as final)
** Broadcaster is using the annotation to be initialized