2004-03-17  Morten Welinder  <terra@gnome.org>

	* src/gutils.c (gnm_string_append_gstring): New function.

	* src/format.c (format_get_decimal, format_get_thousand,
	format_get_currency): Return a GString*.  All callers changed and
	happy since they don't need to call strlen.
	(convert1): Operate of GString.