Tensorboard does not like large event files

assigned to @dl337788

changed milestone to %Official dates

added Bug label

I will not record the average episode length and hyperparameter annealing for now:

• Hyperparameter annealing has been working fine in recent runs and is not dependent on training performance in any way
• At the moment average episode length provides no extra information over the other tracked variables

closed via commit 3ec2f3bc