Docs: break apart the lengthy readme into organized docs

Also sphinx-ify where appropriate, and lots of general cleanup/editing.

docs/contributing.rst

@@ -0,0 +1,54 @@
+Contributing
+============
+
+Djrill is maintained by its users. Your contributions are encouraged!
+
+The `Djrill source code`_ is on github. See `AUTHORS.txt`_ for a list
+of some of the people who have helped improve Djrill.
+
+.. _Djrill source code: https://github.com/brack3t/Djrill:
+.. _AUTHORS.txt: https://github.com/brack3t/Djrill/blob/master/AUTHORS.txt
+
+
+Bugs
+----
+
+You can report problems or request features in
+`Djrill's github issue tracker <https://github.com/brack3t/Djrill/issues>`_.
+
+
+Pull Requests
+-------------
+
+Pull requests are always welcome to fix bugs and improve support for Mandrill and Django features.
+
+* Please include test cases.
+* We try to follow the `Django coding style`_ (basically, PEP 8 with longer lines OK).
+* By submitting a pull request, you're agreeing to release your changes under under
+  the same BSD license as the rest of this project.
+
+.. _Django coding style: https://docs.djangoproject.com/en/dev/internals/contributing/writing-code/coding-style/
+
+
+Testing
+-------
+
+Djrill is `tested on Travis <https://travis-ci.org/brack3t/Djrill>`_ against:
+
+* Django 1.3 on Python 2.6 and 2.7
+* Django 1.4 on Python 2.6 and 2.7
+* Django 1.5 on Python 2.7 and 3.2
+
+The included tests verify that Djrill constructs the expected Mandrill API
+calls, without actually calling Mandrill or sending any email. So the tests
+don't require a Mandrill API key, but they *do* require
+`mock <http://www.voidspace.org.uk/python/mock/index.html>`_ (``pip install mock``).
+
+To run the tests, either::
+
+    python -Wall setup.py test
+
+or::
+
+    python -Wall runtests.py
+