UJOTYP-62 Fix broken generation of project documentation with Sphinx
The behavior of the table of consent has been fixed to display proper leveling depth. Use of a structured way of underlining reStructuredText headings is necessary for this. (see https://www.sphinx-doc.org/en/1.8/usage/restructuredtext/basics.html#sections)
The README.md from the repository root has been converted to reStructuredText version README.rst to allow inclusion into the document generation. This avoids having a second file duplicating the text content and the chance of inconsistencies.