DBus

TODO for DBus integration:

- List all signals, and especially methods that need to be implemented, and list their arguments and return value

- Choose a binding language, since C isn't very friendly for example for objects to be introspectable. QT4 seems nice as it'll soon implement bindings on windows (when DBus for windows is ready) but it's a quite big dependancy. Other options are glib, c++

- Decide what to do when org.videolan service is already registered by another instance of vlc: let the first instance do all the work ? replace it ? place vlc on the queue ?

- Could vlc be a on-demand startable service, would it be useful ?