Bug 17347: Ignore whitespace before and after on renewing

Bug 17347: Ignore whitespace before and after on renewing

When an item is checked out, Koha ignores whitespace
at the beginning and the end of the entered barcode.
This makes life easier, if a barcode is C&P from another
page. This patch makes the renewal page behave the same.

To test:
- Checkout an item
- Renew the item from the renew tab or renewal page
  entering the barcode with leading and trailing
  whitespace
- "Barcode not found"
- Apply patch
- Try again
- Barcode should be found now

Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Devinim <kohadevinim@devinim.com.tr>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>