Refactor document outline

[dnaber-de]

The current document outline is somewhat confusing in a semantic as well as in a visual way:

This button-like highlighting of »Unit tests« is a paragraph and gets followed by an h5 with the text »
Unit Testing and profiling«. So from a readers perspective the headline is duplicated. From a semantic perspective it is one headline and one paragraph that belongs to the section before.

I think we should talk about splitting the content into static pages. Using 5 levels in the outline is an indication that the structure is way to complex.