TASK: Neos Form 6 Compatibility

[adrian-cerdeira]

What I did
I upgraded the package with rector to make it possible to use with Neos Form 6.

How I did it
I used rector from neos.

How to verify it
I used this package in an Neos 9 instance and it worked fine, even if it has the open TODOS.

Checklist

• Can someone resolve the open TODOs?
• The PR keeps backwards compatibility for older versions of Neos if possible.-> I dont think so is possible

[Benjamin-K]

Hi, thanks for this PR. I need to validate the comments in the fusion files, before being able to merge.