rem: void gnibbles_keypress_worms (guint keyval)
add: gint gnibbles_keypress_worms (guint keyval)
context: void gnibbles_keypress_worms (guint keyval){	int i;	for (i = 0; i < properties->numworms; i++)		gnibbles_worm_handle_keypress (worms[i], keyval);}