Feature/prep multimlframeworks

[dstalzjohn]

📥 Pull Request Description

This pullrequest has some breaking changes. Thus, please control it thoroughly. It should help to easier integrate multiple frameworks to niceml like pytorch or hugging face transformers.

There are two things implemented:

• Separation of datasets
• The interface of the learner class is generalized

👀 Affected Areas

Code and documentation.

📝 Checklist

Please make sure you've completed the following tasks before submitting this pull request:

• Pre-commit hooks were executed
• Changes have been reviewed by at least one other developer
• Tests have been added or updated to cover the changes (only necessary if the changes affect the executable code)
• All tests ran successfully
• All merge conflicts are resolved
• Documentation has been updated to reflect the changes
• Any necessary migrations have been run