A TSconfig Reference documentation widget is added.

Resolves: #90438
Releases: master
Change-Id: I8f2a23df420f14c933bf72d82a93356656b7df8d
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/63324


Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: Daniel Siepmann <coding@daniel-siepmann.de>
Tested-by: Richard Haeser <richard@maxserv.com>
Reviewed-by: Daniel Siepmann <coding@daniel-siepmann.de>
Reviewed-by: Richard Haeser <richard@maxserv.com>