* New: Introduce woocommerce_gpf_exclude_variation filter
* New: Introduce "Stock quantity" as a pre-population option
* New: Structured data support for gtin12
* New: Include product feed GUID in review feed as a SKU for better ID matching
* Fix: No not show unnecessary desription headers in variation product feed information block
* Fix: Better product ID support when variable products have IDs set at product & variation level
* Change: Structured data for "condition" uses Schema properties not raw value
