Option to export model training config

[trsvchn]

Currently we store defaults configuration for the project in utils.py.

And as it was discussed, it would be great to add option for the user to be able to dump this configuration (e.g. for reproducibility purpose).

we can make it optional with another flag like:

• [ ] "Store config in a separate file?"

and then, for example, we can ask for the format:

"What kind of config format would you like?"

• [ ] py
• [ ] json
• [ ] yaml