Bug 20688: Add accesskeys for transfers

Bug 20688: Add accesskeys for transfers

To test:
1 - Disable AutomaticItemReturn systme preference
2 - Check in an item that does not float at a branch no it's home
3 - Test new accesskeys for I,N,Y,P
4 - With transfer confirmed check the item in at a wrong branch
5 - Test accesskeys Y,P,X

Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>