…lled anymore...

This point 'basic' training seems to be functional, maybe.
No test data processing, no grad norm clipping, no swa, no metrics, no saving to pb.gz - lots still to do.

…plete save code.

no idea if its output is the right format yet.

…ance

…d to saving.

… no longer be useful, and a fix for swa summaries being written to the wrong file.

…oticeable performance impact.

…de, including upgrade.py which doesn't have an obvious transition.

…sed to work there.

Even if it was working just fine... this seems slightly faster.