Implement wrapper over NeoFS contact's client which allows you to
conveniently interact with the contract. Implement `ManageKeys` method
for binding or unbinding public keys to the NeoFS account.
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
Implement NeoFS contact's client which is responsible for collecting call
arguments and parsing stack items. Initially key binding and unbinding are
supported.
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>