Bug 17826: Allow extended patron attributes to be sent in arbitrary SIP2 fields

Bug 17826: Allow extended patron attributes to be sent in arbitrary SIP2 fields

Some libraries need to be able to send additional patron data from the
extended patron attributes in made up SIP2 fields for the patron
information and patron status responses.

Test Plan:
1) Apply this patch
2) Create 3 new patron attributes with the codes CODE1, CODE2, CODE3.
   Make a least one repeatable.
3) Create a patron, add those attibutes for the patron, make sure there
   are at least two instances of the repeatable code
4) Edit your SIP2 config file, add the following within the login stanza:
   <patron_attribute field="XX" code="CODE1" />
   <patron_attribute field="XY" code="CODE2" />
   <patron_attribute field="XZ" code="CODE3" />
5) Using the sip cli emulator, run patron_information and
   patron_status_request messages for the patron
6) Note the values you set for the patron attributes are sent in the
   corrosponding fields!

Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Daniel Mauchley <dmauchley@duchesne.utah.gov>

Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Amended: added parentheses on line 488 when assigning hashref to array.

Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>