Converted code to use requirejs modules properly.
ignore settings.py
Refactored code to have a physics engine and graphics engine.
I got it back to the point it was before, except that the bullets
now go faster if you click far away and slow if you click near.
The speed isn't actually speed; it needs to be a velocity and thus
have two components: direction and magnitude. This change to be
added later.
Fix speed issue (where shooting far away ccreated faster bullets).
All bullets have same speed now.