Add subpages for Tutorials

[MGlauer]

Implement the subpage for tutorials including pages for the three defined tutorial types:

• [x] Jupyter Notebooks
• [x] Text-based Tutorials
• [x] Video-based tutorials

[MGlauer]

@Ludee: Can you add the mock-up

[MGlauer]

Tutorial overview

[MGlauer]

Video tutorial:

---

Text-tutorial

[Bachibouzouk]

@MGlauer, @johannwagner - What about the work done in #391 ?

[johannwagner]

I do not really have a clue regarding #391. It seems, that @klarareder started to write down some tutorial, but I think, this is not relevant anymore due to the possibility to create tutorials in the backend.

@MGlauer

[MGlauer]

Yes, @klarareder created a tutorial page. We will transfer this page to the new format implemented by @jh-RLI in #478. The problem is, that the approach we used there is not flexible enough to support the community-approach we plan for the OEP.

[MGlauer]

@johannwagner The list of tutorials needs to be improved according to the mockup

[johannwagner]

@christian-rli I assigned you this ticket in order to find a good point in time for fixing up the designs.