Let driver choose subdomain on itslearning.

Hi Michael,

For some reason itslearning won't let me fetch data from itslearning.com directly, but requires me to fetch it from the school's subdomain, absalon.itslearning.com.
I'm guessing that UCPH isn't the only school for which that's the case, so I've added a level of indirection such that the driver now defines which URL to fetch data from.

Cheers,
Michael