docs: Improve wl_display protocol docs
docs: Improve wl_display protocol docs

This adds a bit of information about in-order event delivery,
removes extraneous formatting, and adds a missing period.

bitfactor/wayland,sir-murray/wayland,mchalupa/wayland,bitfactor/wayland,tulcod/wayland,mchalupa/wayland,abooij/wayland,eyolfson/wayland,abooij/wayland,tulcod/wayland,tulcod/wayland,eyolfson/wayland,eyolfson/wayland,mchalupa/wayland,bitfactor/wayland,abooij/wayland,sir-murray/wayland,sir-murray/wayland