Bug 27268: Move GetMarcNotes to Koha namespace

Bug 27268: Move GetMarcNotes to Koha namespace

This patch moves C4::Biblio::GetMarcNotes to
Koha::Biblio->get_marc_notes. This is so get_marc_notes can be
used in templates and notices.

To test:
1. Find a record that has a note (3xx for UNIMARC, 5xx for MARC21).
Confirm the notes still show as normal under the Descriptions tab.
2. Add the record to the cart.
3. View your cart and click 'more details'. Confirm notes show as
normal.
4. Log in to the OPAC. Find the record and add it to the cart
5. View the cart and click 'more details'. Confirm notes show as
normal.
6. View the record detail page and confirm the notes show as normal
under the Title Notes tab.
7. Confirm tests pass:
- t/Biblio.t
- t/db_dependent/Koha/Biblio.t

Sponsored-by: Bibliotheksservice-Zentrum Baden-Württemberg (BSZ)
Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>