Add AABBs to GameObjects
Add a bunch of utility functions

I've moved a lot of information from the pseudo-hacked versions in their source files into
this module in order to clean it up a bit. I've also separated things via comments. Most notably,
our coordinate system will be independent of the screen's coordinate system in order to facilitate
the use of a camera. Our origin will start at the lower right-hand side of the screen, and the
camera is defined by a vector. Obviously the amount of screen that the camera sees depends on the
window size. The scale from screen-space to world-space is 100:1 (i.e. one hundred pixels correspond
to one unit in world space)
Add color vortex and fix python inheritance bugs

This commit is in two parts:
- First, we needed to change the way we were describing our classes in the following files:
    animatedobject.py
    gameobject.py
  We weren't properly inheriting objects due to my (no longer!) limited understanding of python. From there
  we now use the animatedobject's position (inherited from gameobject) in order to determine where it needs
  to be rendered.

- Second, we added the art assets and logic for spinning vortices. I'm terrible at art and it shows in this
  commit. There is a lot of logic in there that is general to sprites in general, and from that we might
  want to extract that into a separate module.