Python bindings of libvlc truncate returned pointers on 64-bit architectures

For functions, like libvlc_media_new_location or libvlc_media_player_new, which return pointers to objects that the python bindings wrap, like Media or MediaPlayer, ctypes need to be told that the return type is a ctypes.c_void_p. Otherwise, it seems to assume the returned value is a 32-bit int and will happily truncate the pointer.

I'll attach a patch for the generator that fixes the problem. The patch depends on another patch I attached to #4678 (closed). I've only been able to test the patch on linux ubuntu 10.10 64-bit with VLC 1.1.4 and a debian squeeze 32-bit with VLC 1.1.3. Also I don't have a complicated enough python app to get full coverage of all the libvlc functions that return pointers. So if anyone can help with more testing that would be great!