Use tqdm() library and remove pytorch_classification Bar

[mikhail]

I removed individual game-specific dependencies as well, though I'd really love to see all these copy-paste files go away and have one top-level file that is configurable (either via main.py file or better yet - some config file inside of game directories!)

This addresses the tqdm bit of #180

[suragnair]

There seem to be some conflicts after merging the logging PR. Also, previously the training steps would print the running loss_pi and loss_v. Would it be possible to incorporate those in the tqdm bars?

[mikhail]

Yep! I'll resolve the conflicts and add those values back as a suffix to tqdm

[mikhail]

Updated! Looks like this now:

[suragnair]

This is awesome! It cleans up a lot of bookkeeping code and hopefully makes the code easier to use. Thanks very much. Would be open to other suggestions for overall repo hygiene.