And shift all miner dbus handling from TrackerMiner. This object
takes a TrackerMiner and implements the org.freedesktop.Tracker1.Miner
interface for it on DBus.

One notable difference in handling here is that libtracker-miner
does not try to own DBus names anymore, that is left up to the caller.
The registered object will be available on whatever dbus name the
caller does register.

For compatibility, all TrackerMiner implementations around have been
made to request their usual name.