Migrate foobar2000 integration

[yhsphd]

Currently the program communicates with foobar2000 using two plugins installed on fb2k: controlserver and beefweb.

But there are issues:

• 2 plugins being needed, beefweb being used for getting most of the data and controlserver to fetch only the album cover, which is inefficient
• controlserver often doesn't even try to send the cover art, the album cover of last song end up being displayed on MusicPlayer.

I'm currently thinking of developing a plugin for KDC from scratch that gathers all of the needed data and sends it to kdc-overlay and migrating the program to use it instead. However, this will involve a lot of changes and currently it's only me that uses fb2k to play music on stream, making this low priority.