Make it clear that the API no longer supports `.../collection/slug`
Make it clear that the API no longer supports `.../collection/slug`

Sinar/popit,openstate/popit,Sinar/popit,mysociety/popit,mysociety/popit,openstate/popit,mysociety/popit,mysociety/popit,Sinar/popit,mysociety/popit,openstate/popit,Sinar/popit,openstate/popit