Martins Erweiterungen
Merge in Martin’s additions

* martin:
  Martins Erweiterungen

Conflicts:
	ausarbeitung/petersen-graph-embedded-on-crosscap.tex
Add a title
Re-work the introduction
Revise Properties section
Re-work the cross cap section
Capitalize caption
Re-work section on embedding

And make linebreaks more semantic :)
Add a section about the dodecahedron construction
Move the greek translation around
Re-work the Maya construction section
Use submission date