Many open source projects use github.com for their contribution process.
Although we mirror the Git core repository to github.com [1] we do not
use any other github.com service. This is unknown/unexpected to a
number of (potential) contributors and consequently they create Pull
Requests against our mirror with their contributions. These Pull
Requests become stale. This is frustrating to them as they think we
ignore them and it is also unsatisfactory for us as we miss potential
code improvements and/or new contributors.

GitHub contribution guidelines and a GitHub Pull Request template that
is visible to every Pull Request creator can be configured with special
files in a Git repository [2]. Let's make use of this!

[1] https://github.com/git/git
[2] https://help.github.com/articles/creating-a-pull-request-template-for-your-repository/

Signed-off-by: Lars Schneider <larsxschneider@gmail.com>
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

* ab/sha1dc-maint:
  sha1dc: update from upstream
  sha1dc: ignore indent-with-non-tab whitespace violations

Update sha1dc from the latest version by the upstream
maintainer[1].

See commit a0103914c2 ("sha1dc: update from upstream", 2017-05-20) for
the latest update. That update was done sans some whitespace changes
by upstream, which is why the diff here isn't the same as the upstream
cc46554..e139984.

It also brings in a change[2] upstream made which should hopefully
address the breakage in 2.13.1 on Cygwin, see [3]. Cygwin defines both
_BIG_ENDIAN and _LITTLE_ENDIAN.

Adam Dinwoodie reports on the mailing list that that upstream commit
fixes the issue on Cygwin[4].

1. https://github.com/cr-marcstevens/sha1collisiondetection/commit/e1399840b501a68ac6c8d7ed9a5cb1455480200e
2. https://github.com/cr-marcstevens/sha1collisiondetection/commit/a24eef58c0684078405f8c7a89f9b78271432005
3. <20170606100355.GC25777@dinwoodie.org> (https://public-inbox.org/git/20170606100355.GC25777@dinwoodie.org/)
4. <20170606124323.GD25777@dinwoodie.org> (https://public-inbox.org/git/20170606124323.GD25777@dinwoodie.org/)

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

The upstream sha1dc code indents some lines with spaces.
While this doesn't match Git's coding guidelines, it's better
to leave this imported code untouched than to try to make it
match our style. However, we can use .gitattributes to tell
"diff --check" and "git am" not to bother us about it.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Signed-off-by: Junio C Hamano <gitster@pobox.com>

Doc update.

* ah/doc-rev-parse-short-default:
  doc: rewrite description for rev-parse --short

Docfix.

* ah/doc-filter-branch-export-env:
  doc: filter-branch does not require re-export of vars

Test fix.

* sd/t3200-typofix:
  branch test: fix invalid config key access

The description strings for a few tests have been updated.

* sb/t5531-update-desc:
  t5531: fix test description

Documentation fix.

* ah/doc-pretty-format-fix:
  Documentation: fix formatting typo in pretty-formats.txt