Don't let speculation constants go negative
Don't let speculation constants go negative

Negative speculation constants cause the amount of time to consider
moves to flip back and forth between positive and negative at increasing
depths. This makes it hard for the constant to evolve back to positive
since it must pass through zero.

MarkZH/Genetic_Chess,MarkZH/Genetic_Chess,MarkZH/Genetic_Chess,MarkZH/Genetic_Chess,MarkZH/Genetic_Chess