draw more per step when at max speed

For a variety of reasons, this took me a lot more time than I expected/it should have.

Things in here:
- a bunch of renaming things. Let me know if you don't like any of the renames.
- moved jumpDistanceCovered from a local variable in the file to instead be on the Turtle object.
- some reworking of drawForwardLineWithPattern_ to handle the case where distance is less than our step size.

Things I tested:
Moving/turning in all directions in frozen both at max speed and not at max speed
drawing all snowflakes at max speed and not.