Move to a logical race model

[DylanRJohnston]

Currently the race model simulates the race based on stats, in an attempt to produce interesting to watch races and "rubber banding" it picks a speed / strength for a certain number of rounds and then repicks it. However this unreliable generates "interesting" races.

Instead the race should be broken into a number of race segments, the overall winner should be calculated based on the stats, and then work backwards for the timing and position of the race segments to produce rubber banding and other interesting race outcomes.