Remove reinventions of the wheel

[dgets]

I'm taking a better look through the import libraries, and it appears that I've tried (often times unsuccessfully, due to the rush to get a bot done before the submission window closes) reinventing the wheel on multiple occasions here. So before anything else, it's time to simplify the code by removing all of that and replacing it with what's already polished.

[dgets]

Looks like I ended up doing this again in commit ee20314, and subsequent commits, in feature/enemy-objective-prediction. It doesn't really matter any more, as there's not going to be nearly enough time left to implement this. If there is a chance to work on the more complex features in this code, though, the collision detection code in the entity.py library will be useful.