[Suggestion] add simple options for transfer learning

[Robolightning]

Hello, I think it would be really cool to be able to retrain your model on new data. It would be great if you could add an easy way to do this in code. Since I'm new in transfer learning at this moment, it's hard for me to figure out how to implement it on your model. I would also be very grateful if you wrote about it, and in this case I would try to figure it out on my own