Fix a problem with the new expr_relocate flag for pasting when soring.

2000-06-05  Jody Goldberg <jgoldberg@home.com>

	* src/cell.c (cell_relocate) : when relocating the expression
	  be careful to use the offsets when calculating the validity.

	* src/workbook-edit.c (workbook_auto_complete_destroy) : Only remove
	  signal if it has been activated.  Only delete the completer if it
	  exists.