Bug 13461 - Circ always asking for confirmation if RentalFeesCheckoutConfirmation...

Bug 13461 - Circ always asking for confirmation if RentalFeesCheckoutConfirmation is used

To test:
- Check RentalFeesCheckoutConfirmation is activated
- Try to check out an item without rental fine
- Verify confirmation message without explanation
  is shown
- Apply patch
- Verify confirmation message is no longer shown
- Configure itemtype to have rental fee
- Veirfy now the confirmation message appears as
  it should

Signed-off-by: Paola Rossi <paola.rossi@cineca.it>
Signed-off-by: Tomas Cohen Arazi <tomascohen@gmail.com>