OCamlPro/opam — pull request #812 by hhugo (2013-09-08 22:00:30+00:00)
Title: fix opam pin with local opam file

* fix: OpamFilename.exists_dir (the semantic was strange)
* fix:
`opam pin pkg path` raise an exception when there is a local opam directory in `path`
* feature:
When pinning, allow to use either "opam/opam" or "opam" as a local opam file