The extension uses TYPO3 core extbase and fluid extensions.
Therefore they should be part of the require.
Otherwise a composer install will lead to an incomplete system setup for
development.
Also add generated files / folders to .gitignore.
Otherwise they might end up in git.
Relates: #8092
Even if the extension is not yet ready.
This is a work in progress, to ease transition we mark it compatible,
so we can easily install, test and adapt before we release.
Relates: #8092
