This is a patch for issue#38.

I have an alternate implementation of this fix which relies on implicitly deriving the GIT root via the git rev-parse --show-toplevel command. This is located on an alternate branch, mklein0/python-versioneer@4bc41f8

I think this is mostly subsumed by #61, which I've been hacking on the last few days (and which is slightly smaller because I think we don't really need to know exactly where the .git directory is: except possibly for installation, Versioneer's git commands can be run from anywhere under the source tree). But I'm adding this to the 0.17 milestone so I don't forget to incorporate the test-coverage and -w wheelhouse fixes from this branch.

Ok, it looks like all the tests from this branch are included in the other one. Closing this in favor of #61.