Reworked headings/titles.

[J-Moravec]

This PR does four things:

• A large amount of empty space around titles is reduced.
• The sections in preface/frontmatter are changed from numbered to unnumbered, but their presence in the TOC is preserved
• The chapter starts are reworked to be closer to the original manual and reduce the blank space
• Small rework of inputs with explanation what individual packages do.

[the3dfxdude]

I'm not sure. I don't think I see much change. But maybe we can tackle the remaining warnings/over/under/fill and with clean up, maybe we can root out the remaining issues.

[J-Moravec]

underflow/overflow/full warnings are diagnostic messages, see: https://www.overleaf.com/learn/how-to/Understanding_underfull_and_overfull_box_warnings

Fixing them is then a question of microtypography and I see it as something you would do at very end.

There are ways to fix it using the microtype package, but again, it will require quite a lot of fiddling. I am trying to concentrate now on bigger problems.

I'm not sure. I don't think I see much change.

Could you be more specific? I can provide you screens. Its probably not obvious (the spacing at least) if you are not looking at both version (pre and post). But if you do, its quite significant change. Sometimes its not perfect due to not enough text for stretching, but that is separate problem that needs to be solved.

[the3dfxdude]

No problem. Your explanation explains it.