message: add function to support the 2 level addressing method
diff: @@ -153,7 +153,7 @@ impl Wallet {
  Some(ref addr) => {
  match addr {
  TxInInfoAddr::Bip44(ref addressing) => self.get_bip44_xprv(addressing),
  - TxInInfoAddr::Level2(ref addressing) => unimplemented!(),
  + TxInInfoAddr::Level2(ref addressing) => self.get_2level_xprv(addressing),
  }
  }
  };
  @@ -271,6 +271,12 @@ impl Wallet {
  .derive(self.derivation_scheme, addressing.change)
  .derive(self.derivation_scheme, addressing.index.get_scheme_value())
  }
  +
  + pub fn get_2level_xprv(&self, path: &[u32; 2]) -> hdwallet::XPrv {
  + self.get_root_key()
  + .derive(self.derivation_scheme, path[0])
  + .derive(self.derivation_scheme, path[1])
  + }
  }
  /// Account associated to a given wallet.
  