Refactor datasets.py module

[ninamiolane]

What?

• [ ] Create a class OSFProject in ioSPI/datasets.py that refactors the code in:
  • the class Project in ioSPI's PR#70
  • the class OSFUpload in ioSPI/datasets.py module
  • the function upload_dataset_from_files of simSPI's tem_tutorial.ipynb
• [ ] Remove the function upload_dataset_from_files of simSPI's tem_tutorial.ipynb
• [x] Adapt the tutorial ioSPI/notebooks/download_and_upload_with_osf.ipynb from ioSPI that upload or download data using the datasets.py module.
• [x] Add corresponding unit-tests.
• [x] Use pre-commit (see README) to make sure that your code follows style guidelines.

Why?

There are several reasons for this task:

• Functionality in ioSPI and simSPI should not be entangled. The fact that they are, i.e. simSPI is using ioSPI, complicates the development: as any PR on ioSPI potentially requires a refactoring PR on simSPI.
• Functionalities that download or upload data with OSF use different logics that are hard to grasp for newcomers: this task creates one Python class only, i.e. one single point of entry with one logic.

• The library ioSPI can only be useful if users can understand it quickly. This task is urgent and very much needed.

Where?

The class OSFProject should go into the ioSPI/datasets.py module.

This class replaces the classes Project and OSFUpload from ioSPI/datasets.py.

How?

The new class OSFProject should have (at least):

• a method ls: listing the files of a OSF project
• a method download
• a method upload

and follow the logic that one object instantiated from this class corresponds to one OSF project.

[bongjinkoo]

I also added remove method. Btw, osf ls does not give us all items in the project. Somehow it doesn't list ones created by the obsolete OSFUpload. I suspect it is because it was added as a child node and osf ls cannot list them, or something. Move on for now, as we will only use osf upload?