wandb config logging

[TimoK93]

Motivation

This PR aims to solve this issue https://github.com/open-mmlab/mmcv/issues/1773 for mmsegmentation. It logs all configs to WandB.

Modification

I added three lines in the train.py script as suggested by https://github.com/open-mmlab/mmcv/issues/1773

As mentioned in the issue, there is no chance to grab the cfg info inside the Logger, so i needed to add in into the train.py file...

BC-breaking (Optional)

No

Use cases (Optional)

Researchers want to filter experiments based on configurations. If you want to filter your experiments in WandB, you need to have some configurations and thus I added the lines.