Got the game-state pack/restore code working. That should let us build a situation-editing tool so that teachers can build situations for students to solve. It's also useful for being able to walk away from a game and pick it up, of course.

Added a quick-and-dirty overview map implementation to the spike test. Need to get a final UI put together some time soon. Need to start documenting how to integrate the game into class plans, what a child can learn from it, that kind of thing.

Would be really nice to get it into a public repository too so that we can get other hackers playing with it.