Serialization: try fix for windows

Author: lmontaut

include/hpp/fcl/serialization/serializable.h

@@ -20,6 +20,9 @@ struct Serializable {
   const Derived& derived() const { return *static_cast<const Derived*>(this); }
 
  public:
+  template <class Archive>
+  void serialize(Archive& ar, const unsigned int file_version);
+
   /// \brief Loads a Derived object from a text file.
   void loadFromText(const std::string& filename) {
     ::hpp::fcl::serialization::loadFromText(this->derived(), filename);