successful and VLC_SUCCESS on success, instead of returning void.

* modules/codec/ffmpeg/encoder.c: ffmpeg doesn't segfault anymore if you set the pts of input frames when doing mpeg4 video encoding.
  So let's use proper PTS now!

 * strip html-like tags from subtitles

- Add "Add group" and "delete group" buttons in the playlistinfo window
- When several items of the playlist are selected, and we change the group, change it for all selected items...

* modules/gui/skins2/x11/x11_factory.cpp: small cosmetic change in a string.

  The V4L panel is now created automatically with an "AutoBuiltPanel" class.
  (A few options are missing compared to the old panel but they need to be added
   to the V4L plugin, not the wxWindows code).

    The XML file must begin with:
    <!DOCTYPE Theme PUBLIC "-//VideoLAN//DTD VLC Skins V2.0//EN" "skin.dtd">
    (the "skin.dtd" is ignored but should be an URL on the website)
    and the DTD is looked up at runtime in the directories of the resource
    path (see previous commit), e.g /usr/local/share/vlc/skins2/skin.dtd
    -> the DTD doesn't need any more to be shipped with the themes.

   to get a list of possible resource directories for skins2.
   On linux the path is "~/.vlc/skins2:VLC_INSTALL_DIR/share/skins2"
   and on win32 it is "VLC_PATH\skins2'
  * src/skin_main.cpp: use the getResourceDir() method instead of #ifdef
  * parser/builder.cpp: the default font is looked up in the resource dir,
   so you can put fonts in ~/.vlc/skins2/fonts and avoid a make install

  + Use ICaptureGraphBuilder2 when available (standard way to setup capture graphs).
  + Extra WDM property sheets for --dshow-config.
  + Some support for selecting crossbar routes.
* THANKS: Added Damien Fouilleul for the DirectShow input improvements.

* modules/gui/wxwindows/menus.cpp: added "Open Capture Device..." and "Preferences..." entries in the popup menu.

   (new variable playlist.isLoop, new commands playlist.setLoop(true)
   and playlist.setLoop(false) in the xml)

  + added a "Open Capture Device..." menu entry.
  + a bit of clean-up.

   controlled by the 'alpha' and 'movealpha' attributes of the 'Theme'
   tag). Win32 only.
   Note: It is advised to use 255 for the alpha value, otherwise resizing
   will be slowed down a lot...

* modules/video_output/directx and x11: implemented VOUT_SET_STAY_ON_TOP in Control()
* src/video_output/vout_intf.c: moved the video-on-top variable there.

* modules/gui/wxwindows/*: fixed auto-generated menus on win32.

when streaming (it's better because of the way sout works).
 * stream_output/stream_output.c: when removing a stream, stop waiting
and start muxing if data are already here (needed for sout with pace
control).

 Both will help to allow muxing (nearly?) all frames, even the last ones.