* Make name and version properties required
* Warn before deleting files in checkpoint directory
* Get default checkpoint path from any logger
* Fix typos
* Uncomment logger tests
* Whitespace
* Update callback_config_mixin.py
checkpoints and version file names would just have a number. it's easy to tell what you're looking at with version_ prepended
* Address comments
* Fix broken tests
* added comet logger
* bug fix in cases where comet was not imported before torch
* fixed mlflow logger to be consistent with docs, updated cometLogger and cometLoggers docs + flake 8 compliance
* Create underlying loggers lazily
This avoids creating duplicate experiments or run in multi-node DDP.
* Save hyperparameters automatically
* Update docs for snapshotting hyperparams
* Fix test tube
* Fix test tube pickling