DOC: Why do we have two README's for contributing?
This one under the documentation folder <a href="https://github.com/pandas-dev/pandas/blob/master/doc/source/contributing.rst">here</a> and this one under the `.github` folder <a href="https://github.com/pandas-dev/pandas/blob/master/.github/CONTRIBUTING.md">here</a>.

I think we should just have one point to the other to avoid having to maintain it in two different places.