message: Add const declaration
diff: @@ -87,7 +87,7 @@ struct Shape {
  // return object transform
  Shape<G, T> *transform(const Pose &pose) const;
  - virtual bool Valid();
  + virtual bool Valid() const;
  virtual Eigen::Matrix<float, Eigen::Dynamic, Eigen::Dynamic> toArray() const = 0;
  @@ -113,7 +113,7 @@ struct Shape {
  };
  template <typename G, typename T>
  -inline bool Shape<G, T>::Valid() {
  +inline bool Shape<G, T>::Valid() const {
  std::string message;
  bool valid = boost::geometry::is_valid(obj_, message);
  if (!valid) {
  