Installation instructions for Readme

[joanwolk]

It would be great to have instructions (e.g., in the Readme) that explain how to include this in a Rails app and in a plain Ruby app.

(I came across this at a hack day, and didn't have time to finish the Moo integration. If I continue later and include it in my Rails app before anyone else has written such instructions, I will submit a pull request.)

[Najaf]

If I continue later and include it in my Rails app before anyone else has written such instructions, I will submit a pull request.

Yes please! 😄