* src/glade-property-class.c: Fixed broken pixbuf properties :)

	* src/glade-widget.[ch]: Added glade_widget_has_launcher &
	  glade_widget_launch_editor.

	* src/glade-parser.c: Fixed segfault (oops).

	* src/glade-editor.c: Use glade_widget_has_launcher &
	  glade_widget_launch_editor (now "Edit..." button comes up
	  for custom editors in the ancestry).