Fix #44

Implement native Debian packaging (control files are part of the source
repo) with Makefile to simplify the release procedure.

RELEASE.rst

@@ -0,0 +1,51 @@
+=================
+Release Procedure
+=================
+
+On your build Pi, perform the following steps:
+
+1. Ensure you have a reliable Internet connection (preferably Ethernet).
+
+2. Ensure you have the following Debian packages installed: ``devscripts, dput,
+   python-all, python3-all, gnupg, build-essential, git, python-setuptools,
+   python3-setuptools, python-rpi.gpio, python3-rpi.gpio``
+
+3. Ensure you have a valid ``~/.pypirc`` configuration. For example::
+
+       [distutils]
+       index-servers =
+           pypi
+
+       [pypi]
+       username:my_username
+       password:my_long_password
+
+4. Ensure you have a valid ``~/.dput.cf`` setup which includes the
+   ``[raspberrypi]`` target. For example::
+
+       [raspberrypi]
+       fqdn = build-master.raspberrypi.org
+       incoming = incoming
+       login = incoming
+       method = scp
+
+5. Ensure you have a valid public/private key-pair defined for GNUPG.
+
+6. In the ``python-gpiozero`` directory, run ``make release``. This will launch
+   ``dch`` to update the Debian changelog. Fill this out properly (ticket
+   references!) and the release will be generated, tagged, signed, and
+   registered with GitHub and PyPI.
+
+   .. note::
+
+       Although the release has been registered at this point, no packages
+       have been generated or uploaded to any service.
+
+7. Still in the ``python-gpiozero`` directory, run ``make upload``. This will
+   generate the actual debian packages, upload them to Raspbian, and upload
+   the source package to PyPI.
+
+8. On GitHub, close any milestone associated with the release.
+
+9. On ReadTheDocs, update the project configuration to build the new release,
+   then set it to the default version for the project.