* Add a prefs button

 - simple screenshot function
 - an helper function to check if the input item is playing 

- vlcshell.cpp: make opengl the default video output module for macosx
- vlc.r: remove Quicktime mimetype from supported list
- configure.ac: the OpenGL provider requires the AGL framework

    automake naming scheme.

(Remove ITEMPLAY method, which had become redundant)

Quit

symbols that would be hidden by the visibility patch, thus allowing VLC usage
with patched FFMPEG code, and sanitise the need for accessing non-public
symbols. Patch by Diego Petteno (flameeyes at gentoo do org).

* First dialog
* Start of input management