Add "(Re-)categorization opportunities" links

[teolemon]

• Add a "Categorization opportunities" link on the Category facet. Useful to populate categories quickly.
  https://fr.openfoodfacts.org/categorie/coteaux-de-tannay

https://world.openfoodfacts.org/cgi/search.pl?action=process&search_terms=coteaux%20de%20tannay&tagtype_0=states&tag_contains_0=contains&tag_0=categories%20to%20be%20completed&sort_by=unique_scans_n&page_size=20

0 opportunities

• Add a "Labelisation opportunities" link on the Labels facet. Useful to populate labels quickly.
  https://fr.openfoodfacts.org/categorie/organic

https://world.openfoodfacts.org/cgi/search.pl?action=process&search_terms=organic&tagtype_0=labels&tag_contains_0=does not contains&tag_0=organic&sort_by=unique_scans_n&page_size=20

6040 products

• Add a "Re-categorization opportunities" link on the category facet. Let's say I'm on the semi-skimmed milks category page.
  Many products might be categorized as Milk and their names might actually be XTRA semi-skimmed UHT milk. We want an easy way to find all products that have UHT milks and semi-skimmed milks categories in their names. This time we don 't exclude already categorized products. This link can be shown on the product page and on the category page

https://world.openfoodfacts.org/cgi/search.pl?action=process&search_terms=uht%20milks&tagtype_0=categories&tag_contains_0=does_not_contain&tag_0=UHT%20milks&tagtype_1=states&tag_contains_1=contains&tag_1=categories%20completed&sort_by=unique_scans_n&page_size=20