Script to set vlc as default player on GNOME desktops. Patch by Torsten Spindler <spindler _at_ tspindler _dot_ de>

Unlock the playlist while waiting for input to finish so that input can freely use signal on the playlist whatever the context is (Closes:#937)

* Possible (not probable) fix for 934. Can't fix as building vlc on win32 is almost impossible

* For the time being, hide simple open. Better three clicks than confusing 
  things :)

The idea is that a given error should be reported only once to the user.
At the moment, for example, we can get:
- "no suitable access module" (printed by module_Need)
 - "unable to create access" (printed by input/access)
 - "unable to open stream" (printed by input/input)
 - ...

The facilities provided here are:
* msg_StackSet( code, message ) : "throw" a new error
* msg_StackAdd( message ) : Append a message allowing to trace the message
* msg_StackMsg() : Retrieve the message

So, in the previous example, module_Need would msg_StackSet( code, "no
suitable access module"), then input/input would add "unable to create
access" and finally, input/input can print the "unable to open stream:
unable to create access: no suitable module" message.

The three functions are context-free, you don't need a vlc_object, so
that we can add verbose error reporting everywhere.

                                   ^^^^^^^^
                   As far as I checked (sed guru required).

code
qt4/components/extended_panels.cpp: Improved some dagerous string
parsing code. This whole function looks very ad hoc to me at the
moment and should be rewritten in a more robust way. In particular
this function will misbehave if a video filter exists whose name is a
substring of another video filter. This change here just makes it less
likely to crash...

Audio track and channel support for JavaScript API. The ActiveX vlc.audio.channel interface still has a bug left.