Bug 24394: Typo when adding a new cash register

Bug 24394: Typo when adding a new cash register

This patch corrects a typo in the cash register template.

To test:
1) Go to Administration > Global system preferences
2) Search for UseCashRegisters
3) Enable UseCashRegisters and save
4) Go to Administration > Cash registers
5) Click on 'New cash register'
6) Notice the title says 'Add new cash_register'
7) Apply patch
8) Refresh and notice it now says 'Add new cash register'

Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>