* Support TYPO3 v12.0
All dependencies are compatible now.
We can update to support v12.0.
This commit will shift TYPO3 support from 10 and 11 to 11 and 12.
See Changelog entry.
Update dev dependencies to our latest best practice.
Auto migrate code base to follow CGL and use PHP 7.4.
Use .gitattributes to tell git what to ignore during exports.
This will prevent GitHub from adding those files to an archive.
Composer will use the GitHub archive as distribution while downloading.
This prevents none necessary files on production systems. This also
reduces file size of archive and should save disk space and other
resources.
