Better systemd integration:
- Run cantata-dynamic as user mpd, group audio (instead of root). This also requires that /run/cantata-dynamic is created by systemd as user mpd doesn't have the necessary right.
- When cantata-dynamic is started, ensure that mpd is started before it.


git-svn-id: http://cantata.googlecode.com/svn/trunk@5583 b1e49159-3266-923f-9c3e-04f16369770a