Use `mpc idle` instead of polling

[Ram-Z]

Would it be possible to use mpc idle or mpc idleloop to update the status instead of polling it every update_interval?

The idea is to reduce the number of useless connections created to mpd. Connections would only needed to be made when something has actually changed on the mpd side and to get the current time when the mouse hovers over the widget.

I could even have a look at it myself, if I find a way to execute functions when mpc idleloop has new output.