/// <summary>
 /// Adds a new signature to this transaction.
 /// </summary>
 /// <param name="signer">object representing a signer</param>
 public void Sign(KeyPair signer)
 {
     byte[] txHash = this.Hash();
     mSignatures.Add(signer.SignDecorated(txHash));
 }
 /// <summary>
 /// Adds a new signature to this transaction.
 /// </summary>
 /// <param name="signer">object representing a signer</param>
 public void Sign(KeyPair signer)
 {
     byte[] txHash = this.Hash();
     mSignatures.Add(signer.SignDecorated(txHash));
 }