Function assign_remainder

include/chaiscript/dispatchkit/operators.hpp:72–75

      template<typename T>
        void assign_remainder(Module& m)
        {
          m.add(chaiscript::fun([](T &lhs, const T&rhs)->T&{return lhs %= rhs;}), "%=");
        }

      template<typename T>
        void assign_right_shift(Module& m)