fixed flashsocket resource handler from outbound to inbound

Hi, seems like the flashsocket ResourceHandler had some problems. It was defined as a ChannelOutboundHandlerAdapter instead of ChannelInboundHandlerAdapter and this was preventing it from receiving any HttpRequest from the socket.io client. Now it should be ok, I tested it with Chrome, Firefox and IE7+ and the handshake worked right establishing a Flashsocket Transport. I also changed the addResource modifier to public to allow resource addition but you can choose to ignore that commit if you think it's not ok...

p.s. this should also fix issue #76.