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...