Default skin becomes slightly transparent when moved.
(deactivated by default, needs to be set up in preferences)

Several redraw were no longer needed
(tested successfully on Ubuntu/metacity and WinNT)

On Win32, switching back and forth between layered Window and not layered
 window (case where only one of the two alpha parameters is < 255) was removed
because display was not satisfactory. (transition a bit weird)

This tiny patch enables opening of VideoCD/AudioCD/DVD discs with VLC in KDE when inserted, which was broken before.
Signed-off-by: Rémi Denis-Courmont <remi@remlab.net>

The default skins now benefits from relative positioning:
   - main window centered
   - playlist window centered with a 5% offset
   - fullscreen controller centered at the bottom
     of the screen with a 3% margin from the border
   - other ancillary windows all centered

So far in skins2, all x, y, width and height were given in pixels, and
no reference to the screen resolution could be made.

This patch implements the following :
- all x, y, width, height can be given in pixels or in % of their container.
  For windows, the container is the screen. For widgets, it can be the
  layout or a panel.
- Five new tags eases up positioning
  - position : relative position given as "Center", "West", "NorthWest", ...
  - x/y-margin : margins to take into account (in px or %) wrt the borders.
  - x/y-offset : additional offset to apply (in px or %).
- the image control can now accept a width and a height parameters.

On most WM, move and resize are noop as long as the window is not visible, and
these calls have to be reissued once the window becomes visible.
  - so avoid unnecessary calls when there are known to be noop.
  - remove a move in TopWindow that appears hackish
    (it hides a MoveResize and is actually needed for _all_ windows)

A good practice is to invalidate the window and leave it to the OS to decide if a repaint is or not needed.

As a side effect, this fixes some alternative task switchers (alt-tab) on WinNT (like TaskSwitcher or ATTv) that displayed a black rectangle instead of the preview of the skin, because the skin engine was not doing things the usual way.

Events like WM_PAINT should be processed in the WinProc, because
some functions directly call the WinProc (e.g UpdateWindow())

Don't do anything if the image doesn't change. Otherwise, some unpleasant
flickering occurs when the image is animated.

All UI related operations in Qt4 must be done on the UI thread, as
QtGui is not thread-safe internally.

LibVLC applications can now select their video memory format when the
video output is created. In particular, this allows preservation of the
original pixel dimensions.

While untested, this should also enable planar YCbCr rendering. Until
this, vmem assumed that all planes had equal pitches, so that subsampled
planes would not really work.

This should fix #3359.

Make sure the specified SDK exists, add a verbose mode, allow to change the default SDK.

Seems like most likely cause to #4078 (reappeared near sametime as toURI was introduced).

This is untested. Doxygen does not seem to work anymore here:
no module lists, no function documentation, only source code.

With this, we can parse an SDP the same way if it comes from SAP
(as sdp://...) or from a file or the network.

Windows CE for example doesn't have this function

Having to type "mux mp2t" was lame

remove obsolete patch forgotten in [4b6e13d3]

RTSP doesn't toggle pause state, it sends unconditional PLAY/PAUSE
commands. Let the VLM handle it.