prefix argument in loggers
🚀 Feature
A simple prefix argument in loggers, similar to what we have in ModelCheckpoint that can prepend this value in metric names.
Motivation
One use-case where I need this is while doing Kfold training. For now, I have to do it manually by updating the metric_name in self.log, but this can be done by the loggers using this prefix parameter. There might be other use-cases too.
Pitch
if prefix='fold1'
and we do self.log('val_loss', ...)
logged metric will be fold1_val_loss.
Let me know if this is a good feature to add :)
cc @PyTorchLightning/core-contributors