Simahawk 20130712 update docs

- updated buildout to 2.0 and `bootstrap.py` links accordingly;
- removed extension of outdated `http://good-py.appspot.com/release/diazo` and pinned latest version into buildout example itself. Tested manually and automatic tests passing;
- fixed broken doc for `proxy.ini` example due to redirect from `http://diazo.org/` to `http://docs.diazo.org/en/latest/index.html`.

Should I have to update also `versions.cfg`?