Dulwich

* Fix hook test on Mac OSX / Linux when dulwich is
not installed system-wide. (Jelmer Vernooij, 919)

* Cope with gecos being unset.
(Jelmer Vernooij, 917)

* Allow adding files to repository in pre-commit hook.
(Jelmer Vernooij, 916)

* Raise SubmoduleEncountered in ``tree_lookup_path``.
(Jelmer Vernooij)

* Support os.PathLike arguments to Repo.stage().
(Jan Wiśniewski, 907)

* Drop support for Python 3.5. (Jelmer Vernooij)

* Add ``dulwich.porcelain._reset_file``.
(Ded_Secer)

* Add ``Repo.unstage``. (Ded_Secer)

* Fix ``dulwich`` script when installed via setup.py.
(Dan Villiom Podlaski Christiansen)

* Make default file mask consistent
with Git. (Dan Villiom Podlaski Christiansen, 884)

* config: disregard UTF-8 BOM when reading file.
(Dan Villiom Podlaski Christiansen)

* Skip lines with spaces only in .gitignore. (Andrey Torsunov, 878)

* Add a separate HTTPProxyUnauthorized exception for 407 errors.
(Jelmer Vernooij, 822)

* Split out a AbstractHTTPGitClient class.
(Jelmer Vernooij)

* Fix installation of GPG during package publishing.
(Ruslan Kuprieiev)