listing the media can potentially hang (changer status), so do not
reload in the background, only on activate
also increase the timeout to 5 minutes and add a reload button
Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
since we do not show the tapes anymore in the BackupOverview, add
another panel where we can list the available tapes in the inventory
Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>