docs: document the enums from mx-types
docs: document the enums from mx-types

pwithnall/mx,jonnylamb/mx,jonnylamb/mx,jonnylamb/mx,clutter-project/mx,jonnylamb/mx,clutter-project/mx,pwithnall/mx,clutter-project/mx,pwithnall/mx,clutter-project/mx,pwithnall/mx