Feature/github issue 24

This addresses *most* of the issues from PullReview (it doesn't yet document all the methods).

The main reason for doing this is to encourage consistency, and so that we can generate and view the documentation like this:

    bundle exec exec rake doc:app
    open doc/app/index.html

I find that helps me feel more obliged to write better docs.

The first 4 commits are ones involving code changes of any substance, the remaining commit (well 3 commits due to my bungling…) contains the mechanical changes such as using `foo: 'bar'` rather than `:foo => 'bar'` in hash initialization.