Naughty Beginnings

Attached is the beginnings of a game that we plan to use to test a new AI being.  This is not the most stringent test, in fact it is a children's game.  At this point, I began coding the solution, but have to run to the lab to put out a fire that the AI being started while throwing a tantrum (and a few technicians).

Get the gist: https://gist.github.com/paegun/8d5950f7c0c523669c8b

Please complete the HumanObserver.display method for a command-line interface (CLI) or HTML interface.

Please don't get distracted by the remaining classes in the overall design.  I was simply blocking out the design ahead.  Once we have the display, I expect the project will iterate rather rapidly.

Thank you.  I look forward to seeing some naughts, crosses, and elegant code.

Background: This is a Ruby adaptation of a interview question that was so popular in the hiring of C programmers that I believe it to be influential in the making of the movie "War Games".