Refresh metadata

Sometimes during version updates, URLs and summaries change. It would be nice if the bot could add these changes as well. This should be possible in Python by running `python setup.py egg_info` inside the sdist and parsing `*.egg-info/PKG-INFO`. There may also be a way to get this info from the PyPI API. Might be possible to pick up on Python version support as well (e.g. is Python 2 supported or now dropped?).

This overlaps to some extent with issue ( https://github.com/regro/cf-scripts/issues/22 ).