Remove tensorboard dependency
🚀 Feature
It would be cool if TB was removed as a dependency, as some people (like me) don't really use it.
Motivation
Tensorboard dependency currently represents close to 50% of the download volume of PL (assuming you start with pytorch installed) - 6.2 MB out of 12.6MB for me, when I install from conda. So removing it would make the package much slimmer.
I use only Wandb for logging - or just the progress bar for quick test runs.
Alternatives
Tensorboard could be put into loggers part of extras_require in setup.py.