full support for _NET_DESKTOP_GEOMETRY
more ICCCM and EWMH support

- full support for _NET_STARTUP_ID
- full support for _NET_WM_USER_TIME
- full support for _NET_WM_USER_TIME_WINDOW
- new windows with an old user time will not steal focus
- full support for WM_TRANSIENT_FOR
- full support for WindowGroupHint in WM_HINTS
- iconifying, activating, hiding and showing  a window performs
  the same actions on its transients