Bug 33231: (Bug 30813 follow-up) No publication date nor edition statements in Z39...

Bug 33231: (Bug 30813 follow-up) No publication date nor edition statements in Z39.50 biblio search results

After executing Z39.50 search, the result table is not populated
with publication dates.  This is the result of code refactoring
made by Bug 30813.  The removed function _add_rowdata treated
in special way the publication date putting it in $row in under
special, non MARC variant dependent key 'date'--since
the z3950_search.tt looks under breeding_loo.date.

Same effect (no data in the result table) with edition statement.
Reason: editionstatement coming from TransformMarcToKoha vs edition
expected by z3950_search.tt.

Test plan:
==========
1. Have a Koha instance with some Z39.50 servers defined.
2. In Cataloging, perform a Z39.50 search for any term.
3. In the result table you would not get the publication dates nor
   edition statement (if present in the record).
4. Apply the patch.
5. Repeat the search.
6. You should see the publication dates (according to the current
   mapping, i.e. for MARC 21 coming from 260 $c or 264 $c subfield)
   and edition statements from the records found.

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>