Bug 3806 - Holidays table doesn't order by date correcly

Bug 3806 - Holidays table doesn't order by date correcly

Adding dateformat filter to JavaScript tablesorter
configurations.

Follow-up adds a custom date parser for dates without year ("01/10")

Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Tested yearly repeatables under Calendar for all three date formats.

Signed-off-by: Paul Poulain <paul.poulain@biblibre.com>
(cherry picked from commit 9a168e7c9451e1960dadbecf83ba937851840310)

Signed-off-by: Chris Nighswonger <chris.nighswonger@gmail.com>