Bandersnatch

- Slight brownbag release: the requirements.txt accidentally included a
development version of py.test due to my usage of mr.developer.

- Fix brownbag release with broken 'stable' tag and missing requirements.txt
update.

- Generate the index simple page ourselves: its not signed anyway and helps
PyPI caching more aggressively.

- Add a py.test plugin to actually show a green bar. Hopefully will be
integrated into py.test in the near future.

- Fix dealing with inconsistent todo files: empty files or with an incorrect
header will just be deleted and processing resumes at the last known good
state.

- Mark up requirement of Python 2.7 `Fixes 19`

- Fix dealing with new CDN cache issues. Thanks to **dstufft** for making PyPI
support mirrors again.

- Improve test coverage.

- Fix packaging: include default config file. (Thanks to **Jannis Leidel**)

- Update pip install documentation to use the a URL for referring to the
requirements.txt directly.

- Adjust buildout and jenkins job to stop fighting over the distribute version
to install.

- Hopefully fixed updating the stable tag when releasing.