0.21.3

0.21.2 -> 0.21.3

Additions:

• Enemy infantry now has an animation

I really don't know how to make animations, so this is a very basic 2-frame "walking" animation, which I created to test the animation code that I might be able to use in the future if I either learn how to do this properly or find someone who'd be willing to help with this. The code is also rather primitive and will more than likely need to be refactored if complex animations are ever introduced. So why did I ship this? Well, the play testers found that the game looks better even with these rudimentary ones, so there you have it.