Add mx-gtk.h to EXTRA_DIST to ensure it is included in releases
Add mx-gtk.h to EXTRA_DIST to ensure it is included in releases

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