Docs: Update documentation (GitHub pages) to include current analysis logic

[berntpopp]

The GitHub Pages documentation (https://halbritter-lab.github.io/kidney-genetics) needs to be updated to include detailed descriptions of each analysis performed:

• [ ] add descriptions of basic input data
• [ ] add descriptions of tools/ APIs/ libraries used
• [ ] add descriptions of re-formating and filtering logic
• [ ] add descriptions of the output format