Improving CONTRIBUTING.md

[faraazahmad]

The current version of CONTRIBUTING.md is pretty bare bones IMO. I would like to know what what challenges you had/have when looking into this codebase for the first time, and what can be done to improve the experience of a first time contributor.

[pknight24]

The hardest part for me was understanding how the tests worked and how to write them, but that was primarily because I had never used RSpec before. Perhaps we could add a link to the documentation in CONTRIBUTING.md.

[faraazahmad]

great idea!

[tacoda]

The Rakefile assumes that you have ruby et al installed locally. Since I use asdf, a few rake tasks did not work for me. I simply worked around them in the terminal, but this is a gotcha for folks using ruby version managers.