Add ext/attrs shortcut for pack/unpack of modules.
Add ext/attrs shortcut for pack/unpack of modules.

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