added option to create private repo (#319)
* added option to create private repo
* added repo_visibility to class
* changed to use private
* Update src/huggingface_hub/repository.py
Co-authored-by: Lysandre Debut <lysandre@huggingface.co>
* changed error message and made private bool and false
Co-authored-by: Lysandre Debut <lysandre@huggingface.co>
