Added documentation location to --help output. I'd prefer if
we included documentation some how in the PyPi package (so it gets
installed) but I'm not sure how best to do that.
Added a script by Douglas Creager for getting the version from
a git tag. This won't work until I make the tag.

This has been modifed to work with "lightweight" tags instead.

See http://dcreager.net/2010/02/10/setuptools-git-version-numbers/
for more details.