Fill out metadata in setup.py

This is in response to issue #321
This is problematic for two reasons:

1. The readme has a lot of stuff in it about setting up virtualenv, etc. This isn't really interesting to someone who's getting the haas via pip install.
2. Reading a file from the local directory actually breaks some things, see #316.

You might look at some other python packages (and the diff between their readme vs. this field) for inspiration.