trivial: Update README to reflect reality
trivial: Update README to reflect reality

superm1/appstream-glib,ikeydoherty/appstream-glib,superm1/appstream-glib,ximion/appstream-glib,ximion/appstream-glib,mitya57/appstream-glib,ikeydoherty/appstream-glib,hughsie/appstream-glib,kalev/appstream-glib,kalev/appstream-glib,hughsie/appstream-glib,mitya57/appstream-glib,hughsie/appstream-glib,ximion/appstream-glib