message: changes for BIG ser/deser
diff: @@ -346,12 +346,13 @@ impl GroupOrderElement {
  }
  pub fn to_string(&self) -> Result<String, CryptoError> {
  - let mut bn = self.bn;
  - Ok(bn.tostring())
  + Ok(self.bn.to_hex())
  }
  pub fn from_string(str: &str) -> Result<GroupOrderElement, CryptoError> {
  - unimplemented!()
  + Ok(GroupOrderElement {
  + bn: BIG::from_hex(str.to_string())
  + })
  }
  pub fn to_bytes(&self) -> Result<Vec<u8>, CryptoError> {
  @@ -527,9 +528,9 @@ mod tests {
  #[test]
  fn serialize_works_for_group_order_element() {
  let structure = TestGroupOrderElementStructure {
  - field: GroupOrderElement::from_string("C4D05C20EC7BAC 2FBB155341552D 6AA4C1EA344257 E84BFFBF1408B3 194D3FBA").unwrap()
  + field: GroupOrderElement::from_string("C4D05C20EC7BAC 2FBB155341552D 6AA4C1EA344257 E84BFFBF1408B3 194D3FBA 0 0").unwrap()
  };
  - let str = r#"{"field":"C4D05C20EC7BAC 2FBB155341552D 6AA4C1EA344257 E84BFFBF1408B3 194D3FBA"}"#;
  + let str = r#"{"field":"C4D05C20EC7BAC 2FBB155341552D 6AA4C1EA344257 E84BFFBF1408B3 194D3FBA 0 0"}"#;
  let serialized = serde_json::to_string(&structure).unwrap();
  assert_eq!(str, serialized);
  