message: null send fix
diff: @@ -136,6 +136,7 @@ std::unordered_map<dev::Address, Vin> QtumState::vins() const // temp
  void QtumState::transferBalance(dev::Address const& _from, dev::Address const& _to, dev::u256 const& _value) {
  subBalance(_from, _value);
  addBalance(_to, _value);
  + if (_value > 0)
  transfers.push_back({_from, _to, _value});
  }
  