IIIF Cantaloupe delegate for Protected Files 

See https://raw.githubusercontent.com/UCLALibrary/cantaloupe-delegate/master/lib/delegates.rb

This is a mix of configurations and delegate writing + Code on Format Strawberryfield to limit via an authentication endpoint + a smart session cookie. 

This is needed if we want to re-use/enforce ACLs and Restrictions defined by Archipelago to deliver Images via Cantaloupe