void SaveBestFit()
{
trainings.Sort(new TrainingComparer());
lastBestFit.Clear();
for (int i = 0; i < nbToKeep; ++i)
{
AIAgent agent = trainings[i].GetComponentInChildren <AIAgent>();
lastBestFit.Add(agent.GetBrainConfig());
}
bestFitness = trainings[0].fitness;
}