Bug 13427: jQuery Timepicker is not translated on returns page

Bug 13427: jQuery Timepicker is not translated on returns page

The returns page was missing an include with the translated strings.

To test:
- Install an additional language, like de-DE
- Confirm the bug on the returns page
  - Make sure SpecifyReturnDate is activated
  - Open the datepicker, look at the time settings
- Apply the patch
- Reinstall the language, no update of the po files is needed
- Retest
- Verify, that now the time settings are translated

Signed-off-by: Josef Moravec <josef.moravec@gmail.com>
Works as expected

Signed-off-by: Jonathan Druart <jonathan.druart@koha-community.org>
Signed-off-by: Tomas Cohen Arazi <tomascohen@unc.edu.ar>