Job cancellation when training time is not sufficient for steps requested.

[cmacfarl]

For the above job, I specified 20 minutes and 2000 steps. There should be some indication that your training job will be cancelled if you don't allocate enough time for all the steps. This indication should appear before the user starts training.

[lizlooney]

I'd like to store a running average of training steps per minute, keyed by number of steps total (because it isn't linear), so we can estimate how long a job will take.