Prototype #57 - Ally AI upgrades

This update brings a swatch of behind-the-scenes changes to AI that make them move more smoothly, react more responsively to the human player's actions, and generally make better decisions. There are also some minor updates like bugfixes and the ability to deflect projectiles with a melee attack. I'm actually concerned the new AI may be a little *too* competent - I'd love to hear your thoughts!