add hooking for WL_SURFACE_ID atom on XWayland windows and composite them

add hooking for WL_SURFACE_ID atom on XWayland windows and composite them

in order to maximize the amount of reused code the following details the current
process for xwayland compositing:

* get map request from window
* force reparenting
* show window
* await WL_SURFACE_ID x11 message
* move x11 client data + pixmap onto corresponding wayland client
* business as usual with wayland compositing

this is pretty similar to the method of the reference code in weston,
except that there's no x11 compositor in weston