Add YARD documentation comments

[roback]

Documented all public methods/attributes using http://yardoc.org/

Started a yard server locally by running

bundle exec yard server --reload

Todo

• [x] Rake task for generating documentation/starting server
• [x] Update readme
• [x] Answer the question: "should documentation be checked in or not?"

[roback]

should documentation be checked in or not?

I have no idea, some keeps it in the repo, some don't.

Im choosing not to as it's one more thing to remember to update each time you make a change. The YARD-comments in the code is still there which should be enough.

[dentarg]

I agree, we should not have the generated documentation in the repo

[dentarg]

:+1:

[jage]

Great job! :+1:

[walro]

Awesome work, left a few minor comments

[roback]

Awesome work, left a few minor comments

"a few" :stuck_out_tongue:

[walro]

:) LGTM!