Finish rework of the compositor, which should fix quite few bugs and improve performance (by discarding damages of covered windows, for example), unredirecting fullscreen overrides seems to work fine which gives a huge performance boost on fullscreen games, fixes translucent xscreensaver window, rework the NET_ACTIVE_WINDOW message handling to improve focus passing (see this thread on the ML http://foo-projects.org/pipermail/xfce4-dev/2006-June/020471.html)

(Old svn revision: 22096)