examples/actor-model: Clean up and comment
examples/actor-model: Clean up and comment

This is an example so it ought to be a bit more didactic.

Distrotech/clutter,jigpu/clutter,Distrotech/clutter,jigpu/clutter,Distrotech/clutter,GNOME/clutter,GNOME/clutter,GNOME/clutter,jigpu/clutter,GNOME/clutter,jigpu/clutter,jigpu/clutter,Distrotech/clutter,Distrotech/clutter,Distrotech/clutter,GNOME/clutter,jigpu/clutter