[TASK] Optimize TypoScriptParser

The code in \TYPO3\CMS\Core\TypoScript\Parser\TypoScriptParser gets called
a lot. It needs to be optimised.

* Use language constructs insted of function calls where possible
* Cleanup method descriptions and parameter defaults

Resolves: #54856
Releases: 6.2
Change-Id: Ia52b3f72393288ed8259b25743a7403260eb5d73
Reviewed-on: https://review.typo3.org/26701
Reviewed-by: Michiel Roos
Tested-by: Michiel Roos
Reviewed-by: Marcin S?gol
Tested-by: Marcin S?gol
Reviewed-by: Jo Hasenau
Tested-by: Jo Hasenau
Reviewed-by: Markus Klein
Tested-by: Markus Klein