[ostree: 16/70] docs/CONTRIBUTING.md: Update for github move, Homu etc.

[Colin Walters <walters src gnome org>]

commit 39777ded54efa94dd78896c50b212ffcbadad7da
Author: Colin Walters <walters verbum org>
Date:   Wed Mar 30 09:19:38 2016 -0400

    docs/CONTRIBUTING.md: Update for github move, Homu etc.
    
    Closes: #230
    Approved by: jlebon

 docs/CONTRIBUTING.md |   45 +++++++++++++++++++++++++++++++--------------
 1 files changed, 31 insertions(+), 14 deletions(-)
---
diff --git a/docs/CONTRIBUTING.md b/docs/CONTRIBUTING.md
index 397ffeb..a26f397 100644
--- a/docs/CONTRIBUTING.md
+++ b/docs/CONTRIBUTING.md
@@ -1,29 +1,46 @@
 Submitting patches
 ------------------
 
-You can:
+A majority of current maintainers prefer the Github pull request
+model, and this motivated moving the primary git repository to
+<https://github.com/ostreedev/ostree>.
 
- 1. Send mail to <ostree-list gnome org>, with the patch attached
- 1. Submit a pull request against <https://github.com/GNOME/ostree>
- 1. Attach them to <https://bugzilla.gnome.org/>
+However, we do not use the "Merge pull request" button, because we do
+not like merge commits for one-patch pull requests, among other
+reasons.  See [this issue](https://github.com/isaacs/github/issues/2)
+for more information.  Instead, we use an instance of
+[Homu](https://github.com/servo/homu), currently known as
+`cgwalters-bot`.
 
-Please look at `git log` and match the commit log style.
+As a review proceeeds, the preferred method is to push `fixup!`
+commits via `git commit --fixup`.  Homu knows how to use
+`--autosquash` when performing the final merge.  See the
+[Git documentation](https://git-scm.com/docs/git-rebase]) for more
+information.
 
-Running the test suite
-----------------------
+Alternative methods if you don't like Github (also fully supported):
 
-Currently, OSTree uses <https://wiki.gnome.org/GnomeGoals/InstalledTests>
+ 1. Send mail to <ostree-list gnome org>, with the patch attached
+ 1. Attach them to <https://bugzilla.gnome.org/>
+
+It is likely however once a patch is ready to apply a maintainer
+will push it to a github PR, and merge via Homu.
 
-To run just OSTree's tests:
+Commit message style
+--------------------
 
-    ./configure ... --enable-installed-tests
-    gnome-desktop-testing-runner -p 0 ostree/
+Please look at `git log` and match the commit log style, which is very
+similar to the
+[Linux kernel](https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git).
 
-Also, there is a regular:
+You may use `Signed-off-by`, but we're not requiring it.
 
-    make check
+Running the test suite
+----------------------
 
-That runs a different set of tests.
+OSTree uses both `make check` and supports the
+[Installed Tests](https://wiki.gnome.org/GnomeGoals/InstalledTests)
+model as well (if `--enable-installed-tests` is provided).
 
 Coding style
 ------------