Enable "copy to selected" for new Curves modifiers

The operator bpy.ops.object.modifier_copy_to_selected()
does not work for the new Curves objects.
This is because it isn't added to BKE_object_supports_modifiers.

Differential Revision: https://developer.blender.org/D15439

source/blender/blenkernel/intern/object.cc

@@ -1402,6 +1402,7 @@ bool BKE_object_supports_modifiers(const Object *ob)
 {
   return (ELEM(ob->type,
                OB_MESH,
+               OB_CURVES,
                OB_CURVES_LEGACY,
                OB_SURF,
                OB_FONT,