Remove almost all instances of GtkCellRenderer in code (all but dnd icon

Remove almost all instances of GtkCellRenderer in code (all but dnd icon

Fri May 25 19:04:17 2001  Jonathan Blandford  <jrb@redhat.com>

	* gtk/gtktreeview.c (gtk_tree_view_calc_size): Remove almost all
	instances of GtkCellRenderer in code (all but dnd icon code).
	Virtualized in GtkTreeViewColumn.  Now I need to move focus in
	there, and I can do multiple Cells per column.

	* gtk/gtktreeviewcolumn.c: Proxy all cell calls correctly

	* gtk/gtktreemodel.c (gtk_tree_row_reference_new_proxy): fix bug
	when model was unreffed prior to removing the row reference.