message: adding an overload to OptFunction
diff: @@ -45,6 +45,10 @@ class OptFunction {
  std::vector<double> &dx) {
  return _function(x, dx);
  }
  + virtual double operator()(const std::vector<double> &&x) {
  + std::vector<double> dx;
  + return _function(x, dx);
  + }
  };
  class Optimizer : public xacc::Identifiable {
  