View source for DBus

TODO for DBus integration:

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


- 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 ?
-- Now if vlc is built with D-Bus >= 1.0.0 it will automatically register org.videolan.vlc, and no other instances of vlc will be allowed to replace it


- Could vlc be a on-demand startable service, would it be useful ?
-- we just have to create a /usr/share/dbus-1/org.videolan.vlc.service:
----
[D-BUS Service]

Name=org.videolan.vlc

Exec=/usr/bin/trunk-build/bin/vlc -I dummy --control dbus
----

Missing features:

volume control => VolumeGet and VolumeSet

playlist => hard.... could we use xspf ?

timing of the input element (position, jump)

preferences ?