Bug 31665: Set today date for date cataloguing plugin

Bug 31665: Set today date for date cataloguing plugin

dateaccessioned.pl must pick today's date when the input gets the focus
on.

Test plan:
Edit an item, or create a new one.
Confirm that today's date is prefilled into the date's input when it's
empty and that it gets the focus on

Signed-off-by: Lucas Gass <lucas@bywatersolutions.com>
Signed-off-by: Michael Adamyk <madamyk@ckls.org>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>