Object can contain public key header. It will be used
for object verification. This header can contain owner's
public key or be the part of x509 chain verification in
couple with verification header.
Tombstone header contains timestamp when tombstone was created.
This timestamp duplicates object creation timestamp in object
system header. This commit removes redundant field.
- SendPutRequest unused and work not like expected
- MakePutRequestHeader should not set epoch / ttl
- remove unused internal functions and consts
- update to latest neofs-crypto
