Added stats_path and played_path options to allow for a proxy between this script and a SHOUTcast server that doesn't return JSON

I added two options that allow for a proxy between one's SHOUTcast server and jquery-shoutcast.js. This is useful if you're running a SHOUTcast server that cannot return JSON yet. (There doesn't seem to be a stable version that does.) In such a case you could create a server side script that converts the SHOUTcast server's XML to JSON.

The original script has `/stats?sid=` and `/played?sid=` hardcoded, but with this change you can overwrite /stats and /played and provide your own path. This could e.g. be a PHP script that converts the SHOUTcast server's XML to JSON(P).