Woo Shipping Class Filter

This plugin adds two sections to the Products table in WooCommerce:

1. A new column for for each product, showing the shipping class defined for that product (or a proper message is there isn’t one defined)
2. A new filter box above the table, where you can choose to filter only the products that have a specific shipping class attached to them. You can also filter all the products with no shipping class at all, as a convenient way of making sure all your products have a shipping class set.

It also adds filtering to the Orders table in WooCommerce with similar capabilities. This feature considers each order to have one shipping class.