The current documentation is not that well structured. Furthermore it is not that easy to update it because there is no direct link to e.g the github page.

I propose to switch the documentation to either Sphinx (https://www.sphinx-doc.org/en/master/) directly or then to the service Read the docs (https://docs.readthedocs.io/en/latest/open-source-philosophy.html) which was built around Sphinx.

Advantages:

• The documentation is automatically built as PDF, HTML and ePub (see the read the docs page on the lower left)
• We can have one documentation per version
• Easier to split up into several chapters
• Motivates other users to extend the documentation because there is always a link to github where a page can be edited
• Better looking than the current documentation (OK. this is subjective)