Add support for usage limited layers in Vertigis Studio Printing

From Vertigis Support:  "Unfortunately, it is not currently possible to print usage limited layers in AGOL. The issue boils down to the way print jobs are executed. When a print is run, VertiGIS Studio Printing makes requests to the map services using a localhost address with a randomized port number. Since this address is not included in the list of referrers (and can't exactly be added since the port number is different every time), the request gets blocked.
 
We do have the issue filed to our bug tracker as 261441…"

A solution using Portal and the new Printing Engine was proposed, but it seems overly complicated for such an essential (no pun intended) capability.