Wipe the LUKS header when deleting a persistent volume
We should make sure that the LUKS header is wiped when deleting the Persistent Storage, to make further forensics more difficult. That is, at least overwritten once with zeroes.
It might be that UDisks does it already, so we should check that first. It might be that UDisks and UDisks2 behave differently in this area, so this should be checked too.
Edited by sajolida