changed `gpointer struct_tm_p' parameter of g_date_to_struct_tm back to

changed `gpointer struct_tm_p' parameter of g_date_to_struct_tm back to

1998-12-02  Sebastian Wilhelmi  <wilhelmi@ira.uka.de>

	* glib.h:
	* gdate.c: changed `gpointer struct_tm_p' parameter of
	g_date_to_struct_tm back to `struct tm *tm' and forward declared
	`struct tm' in glib.h; yes, this is nice, we still need not
	include time.h.