Figure out how we handle 'quiz' type challenges

[escottalexander]

These are just reading assignments but it would be nice to have a set of questions at the end of each one that helps to ensure the user has grasped the concept. Suggestions welcome but we could probably go ahead and build out a quiz type experience within the CLI. Users should be graded on their answers and only pass if they make make a grade better than 80% correct. All of this is subject to new and better ideas.