Merge the coverswitch branch from git://github.com/Zarin/kwin.git (<a href="http://github.com/Zarin/kwin/tree/coverswitch">http://github.com/Zarin/kwin/tree/coverswitch</a>;)

This includes:
* use of RotationData instead of glRotate
* use of x/y/zTranslate instead of glTranslate
* does not define own projection matrix
* changed the direction of the animation (consistent with Cover Flow)
* no special code for start/stop animations.
That's now covered in the code for "normal" switching, thanks to not using glTranslate any more. Therefore
minimized windows are faded instead of moved from panel
* zoom - define how far away the windows appear (only in config dialog possible)
* additional thumbnail bar which is shown when there are many (>= 8, configurable) windows
* window covers can be clicked and become selected window
(Sorry for the one big commit - looking forward to the days when we don't lose commit history when using git ;-))