DOC: modin results "see README"

[rootsmusic]

modin's results are pending, and it says "see README". But README.md doesn't mention modin.

[Tmonster]

Hi rootsmusic,

I'll take a look at this. Might take some time though. If you are curious to see how modin compares, there are instructions on how to run the benchmark in the README, as well as instructions on how to create a PR to update the results. If you look in the pull request history of this benchmark, there should be some examples.

Thanks!