text: Title: Jupyter notebook tutorials: Standardization/streamlining of the notebook format
  Body: - [ ] More linting to check new tutorial notebooks adhere to certain formatting requirements, eg:
  * No outputs of cells.
  * No virtualenv metadata.
  
  See existing linter that checks if notebooks have empty lines:  https://github.com/cleanlab/cleanlab/blob/master/.ci/nblint.py
  
  - [ ] Explanation in [DEVELOPMENT.md](http://development.md/) doc of what steps developer should go through to create a new tutorial, and what the exact formatting requirements are.