Bug 21560: Optimize ODS export of gather_print_notices.pl

Bug 21560: Optimize ODS export of gather_print_notices.pl

Like previous patch, the call on OpenOffice-OODoc lib can be optimized.
Based on https://grep.metacpan.org/search?qci=&q=expandTable&qft=&qd=OpenOffice-OODoc&f=examples%2Ftext2table

Test plan inspired from Bug 11679.

Test plan:
- define your ODUE notice for the print template as:
cardnumber:patron:email:item
<<borrowers.cardnumber>>:<<borrowers.firstname>> <<borrowers.surname>>:<<borrowers.email>>:<item><<items.barcode>></item>
- define overdues rules for a patron category
- check-out 2 items using a due date in order to generate the overdue notices
- check-in these 2 items
- launch the script /misc/cronjobs/overdue_notices.pl
- the 'message_queue' table should now contain 2 new entries
- launch the gather_print_notices cronjob :
  perl misc/cronjobs/gather_print_notices.pl /tmp/test --ods --letter_code=OVERDUE -d=:
- A ods file should be generated in your /tmp/test directory
- Compare times with and without patch

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>

Signed-off-by: Nick Clemens <nick@bywatersolutions.com>