[TASK] update sys_language_uid in TCA & formatting

See merge request !25

https://trello.com/c/3ocgBvPZ/3021-websitebase-alle-erweiterungen-pr%C3%BCfen-und-anpassen-des-tca-f%C3%BCr-syslanguageuid-und-auto-code-format-der-ide-in-den-tca-dateien

VHS was made a requirement with TYPO3 10 now, but for TYPO3 9
compatibility we cannot replace old ViewHelpers yet.
We need to make these replacements with TYPO3 11 then.

[FEATURE] Plugin Previews

See merge request !24

Feature upgrade to typo3 10

See merge request !23

# Conflicts:
#   composer.json
#   ext_emconf.php