Fixed child->icon and child->label == NULL bugs.

Fixed child->icon and child->label == NULL bugs.

1998-01-13  Federico Mena Quintero  <federico@nuclecu.unam.mx>

	* gtk/gtktoolbar.c: (gtk_real_toolbar_style_changed): Fixed
	child->icon and child->label == NULL bugs.

	* gtk/gtktoolbar.h: Added some new functions:
		gtk_toolbar_append_widget()
		gtk_toolbar_prepend_widget()
		gtk_toolbar_insert_widget()
	These let the user insert any kind of widget in the toolbar.  Also
	changed the gtk_toolbar_*_item() functions to return a
	GtkWidget * so that the user can do things with the toolbar buttons.

	* gtk/gtktoolbar.c: Now the toolbar supports its own buttons and
	arbitrary widgets as well.  Geometry management has been changed
	accordingly.  Added gtk_toolbar_remove() function, so container
	functionality should be complete now.

	* gtk/testgtk.c (create_toolbar): Added an entry widget to test
	the new toolbar.

	* Most of these changes are adapted from the
	gtk-lupus-970112-0-patch (should be 970112... :-)