as well as tooling and docs to generate this for each release
Also moved Cython files to package_data, so that we install them,
instead of just packaging them.
versioneer let's us track the version using git tags. This prevents
issues like the 0.8.2->0.8.3 push. This also puts the number of commits
from the release and the commit you are on in the version.
Scott Sanderson