Openseadragon requests images from Cantaloupe as anonymous

[dannylamb]

Currently, Openseadragon makes no attempts to provide credentials when requesting images from Cantaloupe. If files on Drupal are properly restricted, then even when going to a page as admin, you'll get a 403 in the Openseadragon viewer. Drupal is requiring its JWT token in the Authorization header from the AJAX request that Openseadragon sends.

This can be accomplished in two parts:

1. Adding the Authorization header to the AJAX request by properly configuring the Openseadragon viewer
2. Adding a delegate script to Cantaloupe that passes along the Authorization header so it's available to the HttpSource

[seth-shaw-unlv]

Nice! We've worked around it by simply adding a context condition that only uses the OpenSeadragon viewer when the media is accessible by Anon, but getting it to work with authenticated users is the right way.