services_discovery.c: Patch by Alexander Gall <gall # switch.ch>, avoid crashing on systems that don't handle NULL string in ..printf.

cosmetics.

Fix some segfaults by disabling functions.
Slower, faster are on the side of the slider now.

 - Don't use the .ui, do all by hand :)
 - Use a ControlWidgets to design all the controls, and implement the functions
 - Change a bit the advanced widget, that must be integrated in the
   controlsWidget
There is a lot of Not Yet Implemented, so feel free to add some.

Redesign the label & edits placement to resize the dialog

control/dynamic_media_list.c: New dynamic media list object. It shouldn't have great performances, but could easily be improved.
The idea is to have create a media list using the item of an other that matches a certain query.

* control/media_list.c: Implement _set_name _add_from_file.