Bug 33030: Add standardized subroutine for processing Template Toolkit syntax outside...

Bug 33030: Add standardized subroutine for processing Template Toolkit syntax outside of notices

Koha has evolved to use Template Toolkit for many uses outside of generating slips and notices for patrons. Historically, each of these areas processed template toolkit in a slightly different way. We should add a module to allow Template Toolkit syntax to be processed in a standard and generic way such that all non-notice TT syntax is handled and processed the consistently.

Test Plan:
1) Apply this patch
2) prove t/db_dependent/Koha/Items.t

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>