Limit the number of generations that can occur in a single tick, forcing them
to be spread out more.
Defaulting to 10 as an average generation is going to be 3-6ms, which means 10 will
likely cause the server to lose TPS, but constrain how much.
This should result in no noticeable speed reduction in generation for servers not
lagging, and let larger servers reduce this value according to their own desires.
