Bug 22932: GetLatestSerials should not return formatted date

Bug 22932: GetLatestSerials should not return formatted date

This patch updates GetLatestSerials in Serials.pm to remove date
formatting. Formatting of dates should be done in the template using
$KohaDates.

To test, apply the patch and locate a bibliographic record in the staff
client which has a subscription with issues.

 - On the bibliographic detail page for that record, view the
   "Subscriptions" tab. Dates in the table of recent issues should be
   formatted correctly.
 - View the details for the subscription in the Serials module. Create
   or edit a routing list for that serial. In the "Issue" dropdown the
   issue dates should be formatted correctly.
 - View the bibliographic detail page for the record in the OPAC. Open
   the "Subscriptions" tab. In the table of recent issues publication
   date and received date should be formatted correctly. The table
   should sort correctly on these dates.

Note: Although opac-ISBDdetail.pl calls GetLatestSerials, as far as I
can tell there is no serial-related output to update. The code appears
to be unused.

Signed-off-by: Maryse Simard <maryse.simard@inlibro.com>
Signed-off-by: Josef Moravec <josef.moravec@gmail.com>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>