Bug 7567: (follow-up) Modify DataTables configuration

Bug 7567: (follow-up) Modify DataTables configuration

This follow-up corrects a JavaScript error by converting the sorting
configuration to be class-based
(http://wiki.koha-community.org/wiki/DataTables_HowTo#Sorting_dates_regardless_of_date_format_preference).

I have also changed the DataTables configuration to allow for pagination
and JS-based filtering.

To test, apply the patch and view the list of News items. Your browser
should report no JavaScript errors. Table sorting, pagination, and
filtering should work correctly.

Signed-off-by: Jonathan Druart <jonathan.druart@biblibre.com>
Signed-off-by: Galen Charlton <gmc@esilibrary.com>