Add support for showing producer provided and protected fields

[teolemon]

Problem

• Add support for showing producer provided and protected fields
• A new version of the OFF website has been deployed. It contains in particular a change to the product edit form, to highlight which values have been provided by the manufacturer. Those values can be changed only by moderators, but previously it was not indicated and that caused users to waste time and efforts trying to change things that could not be changed. e.g. reported on the forum: https://forum.openfoodfacts.org/t/some-products-cannot-be-modified-vendor-lock/594
• It's this field https://fr.openfoodfacts.org/produit/3017620425035/nutella-ferrero.com?fields=owner_fields
• On the other hand it contains tag type fields, they must be ignored because the value could have changed afterwards and it is not protected

Mockups

Part of

• Contribute (Tracker) #503