Single mode toggle is originally done with Y which I can't remember.
Usually I activate single mode only by accident and so I created this
custom binding to override the default.
Also added P binding to save the playlist, which is S per default.
Added mpdconf. This file contains an include of ~/.mpdconf.local
which contains the listen directive.
Added a basic ncmpcpp config - mostly because a few keybindings
for daily usage that I really got used to.