This module now fetches a https stylesheet and returns it as a
string to Base. (As a workaround waiting for a real solution
in the underlying libraries.)
The module can be extended to resolve includes but this requires
parsing the xslt code.
Test plan:
[1] Run t/Koha_XSLT_HTTPS.t
Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl> Signed-off-by: David Nind <david@davidnind.com> Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com> Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>