README: Move development information to a separate file in /Documentation

Move the development information to "Developer Guide" under the
documentation folder, and link to it from README.

Later changes will add another separate document for configuration.

Change-Id: Iee66f26ea21c98667faa0ebe5f8e19e6501d9638

Documentation/developer-guide.md

diff --git a/Documentation/developer-guide.md b/Documentation/developer-guide.md
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+# Developer Guide
+
+[TOC]
+
+## Building
+
+Gitiles requires [Buck](http://facebook.github.io/buck/) to build.
+
+```
+sudo apt-get install ant
+cd ${HOME}
+git clone https://github.com/facebook/buck.git
+cd buck
+ant
+sudo ln -s ${PWD}/bin/buck /usr/bin/buck
+cd /path/to/gitiles
+git submodule update --init
+buck build all
+buck test
+```
+
+
+## Testing
+
+```
+cd /path/to/repositories  # Don't run from the gitiles repo.
+/path/to/gitiles/tools/run_dev.sh
+```
+
+This will recompile and start a development server.  Open
+http://localhost:8080/ to view your local copy of gitiles, which
+will serve any repositories under `/path/to/repositories`.
+
+To run unit tests, run `buck test`.
+
+
+## Eclipse IDE
+
+If you'd like to use Eclipse to edit Gitiles, first generate a project file:
+
+```
+./bucklets/tools/eclipse.py --src
+```
+
+Import the project in Eclipse:
+
+```
+File -> Import -> Existing Projects into Workpace
+```
+
+The project only needs to be rebuilt if the source roots or third-party
+libraries have changed. For best results, ensure the project is closed in
+Eclipse before rebuilding.
+
+
+## Code Style
+
+Java code in Gitiles follows the [Google Java Style Guide][java-style]
+with a 100-column limit.
+
+Code should be automatically formatted using [google-java-format][fmt]
+prior to sending a code review.  There is currently no Eclipse
+formatter, but the tool can be run from the command line:
+
+```
+java -jar /path/to/google-java-format-1.0-all-deps.jar -i path/to/java/File.java
+```
+
+CSS in Gitiles follows the [SUIT CSS naming conventions][suit].
+
+[java-style]: https://google.github.io/styleguide/javaguide.html
+[fmt]: https://github.com/google/google-java-format
+[suit]: https://github.com/suitcss/suit/blob/master/doc/naming-conventions.md
+
+## Code Review
+
+Gitiles uses Gerrit for code review:
+https://gerrit-review.googlesource.com/
+
+Gitiles uses the ["git push" workflow][1] with server
+https://gerrit.googlesource.com/gitiles.  You will need a
+[generated cookie][2].
+
+[1]: https://gerrit-review.googlesource.com/Documentation/user-upload.html#_git_push
+[2]: https://gerrit.googlesource.com/new-password
+
+Gerrit depends on "Change-Id" annotations in your commit message.
+If you try to push a commit without one, it will explain how to
+install the proper git-hook:
+
+```
+curl -Lo `git rev-parse --git-dir`/hooks/commit-msg \
+    https://gerrit-review.googlesource.com/tools/hooks/commit-msg
+chmod +x `git rev-parse --git-dir`/hooks/commit-msg
+```
+
+Before you create your local commit (which you'll push to Gerrit)
+you will need to set your email to match your Gerrit account:
+
+```
+git config --local --add user.email foo@bar.com
+```
+
+Normally you will create code reviews by pushing for master:
+
+```
+git push origin HEAD:refs/for/master
+```