Remove position encoding

[jacobbieker]

Pull Request

Description

|Position encoding isn't being used at all, so can be removed. Also removes SatFlow Dataset and DataModules as they haven;'t been used in a long time, and if we needed them we could always readd them.

Fixes #127

How Has This Been Tested?

Unit tests

• [x] Yes

If your changes affect data processing, have you plotted any changes? i.e. have you done a quick sanity check?

• [ ] Yes

Checklist:

• [ ] My code follows OCF's coding style guidelines
• [ ] I have performed a self-review of my own code
• [ ] I have made corresponding changes to the documentation
• [ ] I have added tests that prove my fix is effective or that my feature works
• [ ] I have checked my code and corrected any misspellings