Please add support for ISBN

The plugin currently supports EAN, GPC, and MPN. In my shop, I also sell three different books. Each of it has an ISBN number. An ISBN number is not an GPC or EAN.

Could the plugin also add support for “ISBN”?

See https://www.amazon.com/gp/seller/asin-upc-isbn-info.html/ref=DE_SOA_FAQ_requirements_helplisting?ld=ASDESOADirect for details.