by checking for definedness of the label (tapes without barcode
have the empty string as label-text) and falling back to the
source slot for the load action
Note: Changed the load-slot API from PUT to POST
Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
Signed-off-by: Dietmar Maurer <dietmar@proxmox.com>