[Plugin: Icecast Now Playing] patch for ajax call

Hello,

I wrote a patch for icecast-now-playing to make request to icecast server via ajax. This significantly increase page generation if icecast server is not on the same host as web server. And it also make it easy to periodically refresh the information (every 30 seconds).

Everything is there: https://pastebin.com/XHCm2eLg

https://www.ads-software.com/extend/plugins/icecast-now-playing/