Add resuming from specific checkpoint
Is your feature request related to a problem? Please describe.
In current version, there is no way to resume training from a specific checkpoint (not the last checkpoint).
Sometimes (very often in my case), one needs experiment training with different hyperparameters (e.g. dropout rate, augmentation) from a specific checkpoint.
Describe the solution you'd like
Add resume_from_checkpointargument to Trainer class.
Describe alternatives you've considered
I tried to use restore from Trainer class, but was not successful because it is meant to be used only when .fit() is called.
Additional context
FYI, I made a PR to demonstrate my idea: #516