A3C episode length unbounded

[mkisantal]

Episodes are not terminated when episode_step_count exceeds max_episode_length.

It is not necessarily a problem, but as both summary writing and model saving is dependent on episode_count, if the episodes are getting too long then these actions are less frequent.

In my case (I'm using the algorithm with a different environment, not doom), as the agent got better episodes exceeded 8000 steps, so that really influenced the model saving frequency.