Population Diversity Tracker

[jamesbevins]

We should implement a population diversity tracker to ensure that we aren't loosing diversity over time. An adaptive algorithm that resamples if diversity is lost would likely improve performance. The trick is that some loss of diversity, especially late time, can speed convergence.

[jamesbevins]

Good starting paper: http://link.springer.com/chapter/10.1007/3-540-45110-2_21