Fix some issues in pprintast and untypeast.  Patch by Jun Furuse (with minor modifications), from github #70.

git-svn-id: http://caml.inria.fr/svn/ocaml/version/4.02@14956 f963ae5c-01c2-4b8c-9fe0-0dff7051ff02
Typo.

git-svn-id: http://caml.inria.fr/svn/ocaml/version/4.02@14957 f963ae5c-01c2-4b8c-9fe0-0dff7051ff02