Adding implementation for serving a Flash Socket Policy on the destination port

In order to support using Flash Socket as a fallback for browsers who do not support websockets, a Flash Socket Policy File must be provided. They are 2 main ways to provide it. The target server, the one listening for incoming websockets connections must provide it by listening on port 843. The other possibility is to provide the Flash Socket Policy File on the destination port, the port used for websockets.

This change implements the second option where the Flash Socket Policy is provided on the destination port. See https://github.com/gimite/web-socket-js for the most popular Flash Socket fallback for websockets, http://www.lightsphere.com/dev/articles/flash_socket_policy.html for some details about the Flash Socket Policy setup and http://www.adobe.com/devnet/flashplayer/articles/socket_policy_files.html for even more details by Adobe about the use and installation of the Flash Socket Policy.