message: get the TxIn by reference
diff: @@ -52,7 +52,7 @@ impl<T: AddressLookup> State<T> {
  Ok(())
  }
  - pub fn forward_with_txins<I: IntoIterator<Item = TxIn>>(&mut self, iter: I) -> Result<Vec<Log<T::AddressOutput>>, T::Error>
  + pub fn forward_with_txins<'a, I: IntoIterator<Item = &'a TxIn>>(&mut self, iter: I) -> Result<Vec<Log<T::AddressOutput>>, T::Error>
  where T::AddressOutput: Clone
  {
  let mut events = Vec::new();
  