Bug 16941: Can not add new patron in staff client

Bug 16941: Can not add new patron in staff client

To reproduce:
- Go to staff client Home > Patron
- New patron
- Choose a category and fill form, submit
Result: Form reloads, patron data are not saved.

To test:
- Apply patch
- Repeat steps above
- Verify that patron data are saved and the new patron's
  detail page displays
- Try to enter a duplicate patron (e.g. same surname, firstname
  and birthday as above)
- Verify that a duplicate message appears

Signed-off-by: Hector Castro <hector.hecaxmmx@gmail.com>
Works as advertised

Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>