Workflow/Template: Sciebo features Overleaf now: Switch from self-made tooling to Overleaf?

[cagix]

see cagix/faq-praxisphase-abschlussarbeit#45:

Idea: Create a genuine TeX template and make it compatible with Sciebo-Overleaf (= base). Adapt the tooling here so that it uses this TeX template, plus Docker with Pandoc, LaTeX, filters, ... (= extension).