[ew:bs] Rewrite semantics section
[ew:bs] Rewrite semantics section

- remove how axiom annotations are translated in detail
- add url of array theory source in footnote
- add meaning of the set symbols that are used in the array axioms
- clarify why assertions for array access and division are used

- rename subsection Funktionsverträge to Funktionsdefinition
- rename subsection Arrayzugriffe to singular Arrayzugriff
- rename subsection "Kontext für einzelne Annotationen" to
  "Abbildung von freien Variablen nach Bedeutungen"
- rename subsection Typsystem to Typprüfung

- add subsection for treatment of function calls in check*()
- add subsection for treatment of formulas in checkAnnotation()
- add subsection for treatment of uninitializeds in checkProgram()

- put axiom numbers in the formula list also in brackets

team-worthwhile/worthwhile,team-worthwhile/worthwhile