VLCMediaList.m: Don't mess between node hierachical and hierarchical cached copy of the MediaListAspect.

MacOSX/VLC_app: Initial import. Big playlist still causes memory and cpu high load. Interface is ugly. Miss many functionality. But code is light. Supports multiple player. Fullscreen a-la frontrow interface (yet a bit ugly).

MacOSX/Framework: Support event collapsing, and save the media list thats own the media list aspect.

VLCMedia.m: Don't flood the event manager with unused meta change notification. Remove uneeded willChangeValueForKey: notification, as per Julien Robert suggestion.

v4l2: Factorize code, fix the video controls init, add Dennis Lou's contributions to the v4l2 module in THANKS.

macosx: if an input item includes a NowPlaying meta item, display it in our controller window instead some bogus MRL parsing stuff nobody can understand

misc/events.c: Fix event sending, by properly supporting event_manager edition (event_detach) while executing a callback (vlc_event_send). This is done through a recursive lock.

macosx: added an option to disable the 'Recent Items' list as requested by multiple forum users (closes #1340)

it.

You can not change a playlist_item_t to be a node, when you previously registered events on it, using input_item_t sub items adding event, because the pointer will be destroyed.
If you want to use nodes anyway, you have to explicitely create them.
Note: we were lucky that xspf did work so far, because we were EXCLUSIVELY using invalid pointers, except for the 1st item being added to each playlist_item_t (it did happen before the conversion obviously).

macosx: don't allow the user to open the preferences window multiple times (leading to orphan pref windows which can't be controlled)