Since it was made DBus activatable having any other code to start/stop
the daemon doesn't really make any sense. For that reason I've
moved it to libexec.
Also the original code is somewhat questionable. It creates a whole qapp
instance, checks if we're registered then forks itself to spawn a new
version of the app that then registers.
KDBusService already does all this in a simpler faster non-racey way.