Decide if logger and trainer should be combined #7
Description
From PR #2 the logger and trainer classes are two separate objects but they are obligated to be created and used together, which raises the issue of whether they should be combined.
Pros:
- less moving parts
- callbacks access trainer directly
Cons:
- more difficult in the future to develop drop-in replacement alternative logging/experiment management backbones (if we ever want to do that)