Add a development documentation.

docs/docs/development.rst

@@ -0,0 +1,38 @@
+.. include:: ../global.rst
+
+Development
+===========
+
+If you want to contribute anything to |parso|, just open an issue or pull
+request to discuss it. We welcome changes!
+
+
+Deprecations Process
+--------------------
+
+The deprecation process is as follows:
+
+1. A deprecation is announced in the next major/minor release.
+2. We wait either at least a year & at least two minor releases until we remove
+   the deprecated functionality.
+
+
+Testing
+-------
+
+The test suite depends on ``tox`` and ``pytest``::
+
+    pip install tox pytest
+
+To run the tests for all supported Python versions::
+
+    tox
+
+If you want to test only a specific Python version (e.g. Python 2.7), it's as
+easy as::
+
+    tox -e py27
+
+Tests are also run automatically on `Travis CI
+<https://travis-ci.org/davidhalter/parso/>`_.
+