Document the shell.configure event a bit
Document the shell.configure event a bit

tulcod/wayland,Tarnyko/weston-xdg_surface_present,eyolfson/weston,kwm81/weston,Fantu/compositor-spice,eyolfson/wayland,Fantu/compositor-spice,giucam/weston,sir-murray/weston,tulcod/wayland,mchalupa/wayland,eyolfson/weston,abooij/wayland,krezovic/weston,sir-murray/wayland,tulcod/wayland,xorgy/weston,mchalupa/weston,udoprog/weston,Fantu/compositor-spice,bitfactor/wayland,udoprog/weston,eyolfson/wayland,Gnurou/weston,abooij/wayland,mchalupa/wayland,xorgy/weston,jonnylamb/weston,mchalupa/weston,Tarnyko/weston-xdg_surface_present,sir-murray/wayland,giucam/weston,jonnylamb/weston,abooij/wayland,mchalupa/wayland,eyolfson/wayland,kwm81/weston,Gnurou/weston,sir-murray/wayland,krezovic/weston,sir-murray/weston,bitfactor/wayland,bitfactor/wayland