PDF-emitter: UserProperties like standard configuration at designer level

[speckyspooky]

The PDF-emitter provides a large set of user properties to handle special handling options like the prepend or append of PDF document.
Further options are the setup of PDF version or the configuration of PDF/A.
The challenge is to know that this options exists.

Thefore the idea is to add these options like configuration options directly at the designer.
A configured user propery has higher priority instead of the designer configuration to keep the current handling.

Screen of the available options on designer level, register "Advanced"

I will provide a PR for that enhancement.

[speckyspooky]

The change is added with PR #1845 and merged to the master branch.