Update to 3.1.1 XSD and Codelists 66

[mcxigxag]

Hi - thanks for creating this really useful utility!
I wonder if you would be able to update the xsd to the latest 3.1.1 and Codelist 66 editEUR spec?
There are only a few publishers using the new spec but when they do, I get false negatives on codes that aren't known.

I think this is a relatively simple change but I'm afraid I'm not able to suggest a PR for you.

https://www.editeur.org/93/Release-3.0-and-3.1-Downloads/#Schemas

Many thanks.