Bug 31986: Add page-section to various administration pages

Bug 31986: Add page-section to various administration pages

This patch adds a page-section div to some administration pages in order
to provide a consistent structure visual contrast. The following pages
are modified:

Additional fields
Funds
Authority types
Authority types -> MARC tag structure
Authority types -> MARC tag structure -> Subfields
MARC bibliographic framework
MARC bibliographic framework -> MARC tag structure
MARC bibliographic framework -> MARC tag structure -> Subfields
MARC Bibliographic framework test
Classification configuration
Currencies and exchange rates
EDI accounts
Library EANs
Item search fields
Koha to MARC mapping
Record overlay rules
Record matching rules
OAI sets configuration
SMTP servers
Z39.50/SRU servers

To test, view each page to confirm that the page-section div visibly
delineates the main content area.

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>