resume from checkpoint function is not working

[jo7ueb]

Describe the bug

resume_from function is introduced in #31. But now this function is not called by anybody, makes it not working.

Expected result

resume_from is called by generated code, allows to user to resume training from checkpoint.

Reproduction

1. Generate code (in my case I used vision classification template)
2. Watch around the generated code
3. You'll find nobody callls resume_from, makes unable to resume from checkpoints.

[vfdev-5]

@jo7ueb resume_from is a helper method to resume the training. It is not used by default as we are not resuming a training but start from the beginning.

resume_from is called by generated code, allows to user to resume training from checkpoint.

How would you think it should be called in main.py::run method ?