New function to obtain a list of toplevel widgets constructed by the ui

New function to obtain a list of toplevel widgets constructed by the ui

Fri Jan  9 00:34:57 2004  Matthias Clasen  <maclas@gmx.de>

	* gtk/gtkuimanager.h:
	* gtk/gtkuimanager.c (gtk_ui_manager_get_toplevels): New function to
	obtain a list of toplevel widgets constructed by the ui manager.

	* gtk/gtkuimanager.h (GtkUIManagerItemType): Change to flags, so that
	the values can be combined for gtk_ui_manager_get_toplevels().

	* tests/testmerge.c: Add a "Dump toplevels" button to test
	gtk_ui_manager_get_toplevels().