xfwm4-wayland

Hi

I have rebased my Wayland port of xfwm4 onto the latest xfwm4 master.

I have also scrubbed my meson.build from my commit history and added
Wayland support to the new meson.build from xfwm4 master, so that my
meson.build won't clutter up the commit history.

Here is the git repo:
https://github.com/adlocode/xfwm4/tree/wayland

Regards

adlo