Derive Macro bee_common_derive::SecretDrop

#[derive(SecretDrop)]

Derives an implementation of the trait std::ops::Drop for a secret type that calls Zeroize::zeroize. Implements https://github.com/iotaledger/bee-rfcs/blob/master/text/0044-secret-zeroize-drop.md. Based on https://github.com/dtolnay/syn/blob/master/examples/heapsize/heapsize_derive/src/lib.rs.