[TASK] Clean up RTE docs and TSconfig

There are several options that are included
in the RTE configuratoin which are not
related to RTE, or which are set by default.

Also, the documentation is updated to reflect
the options available in the RTE.

Resolves: #77784
Releases: master
Change-Id: Iabfbcad51afe822bbe18779d9239cbbdb8d49d6b
Reviewed-on: https://review.typo3.org/49756


Tested-by: Bamboo TYPO3com <info@typo3.com>
Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Tested-by: Wouter Wolters <typo3@wouterwolters.nl>
Reviewed-by: Andreas Fernandez <typo3@scripting-base.de>
Tested-by: Andreas Fernandez <typo3@scripting-base.de>