modify documentation of Stack.fold
modify documentation of Stack.fold

msprotz/ocaml,msprotz/ocaml,gerdstolpmann/ocaml,yunxing/ocaml,msprotz/ocaml,eliberis/ocaml,yunxing/ocaml,gerdstolpmann/ocaml,gerdstolpmann/ocaml,eliberis/ocaml,eliberis/ocaml,msprotz/ocaml,msprotz/ocaml,gerdstolpmann/ocaml,yunxing/ocaml,yunxing/ocaml,eliberis/ocaml,gerdstolpmann/ocaml,eliberis/ocaml,yunxing/ocaml