Bug 12377 - Add date pickers to serials-edit.pl

Bug 12377 - Add date pickers to serials-edit.pl

There are two date fields when receiving serials on serials-edit.pl,
these inputs should have a calendar widget like other date fields
in Koha.

Test Plan:
1) Apply this patch
2) Recieve a serial
3) Note when clicking on the "Published on" or "Expected on" fields
   you will now have a calendar popup. Note you can still manually
   edit the date if you wish to.

Signed-off-by: Aleisha <aleishaamohia@hotmail.com>
Signed-off-by: Jonathan Druart <jonathan.druart@biblibre.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@gmail.com>