Video: Dropped old XV, X11 and DX complex code.

This is now replaced by simpler GStreamer/Clutter code.
Video: Simplified code again.

The videooutput-info.h file was removed as we do not need it anymore.
Output statistics have been removed.
Error codes have been removed from the output manager too. There was
only one type of error possible.
All references to DisplayInfo have been removed (or commented out for
further processing).