Cover art improvements

Recently version 2.17 of libmpdclient was released which adds support for binary responses, like for the ‘albumart’ command that was added to mpd a while ago. Using this new library version Rigelian can now read local cover art without requiring a http server on the player.

There are still two major limitations with this approach:

• It only works with mpd version 0.20.10 and up. Many players are still on older versions.
• It requires that the artwork file is named cover.jpg or cover.png.

Support for this will be in the next Rigelian version, along with some other improvements in the artwork department.