message: changed to_device_type_impl specializations to allow const pointers
diff: @@ -239,6 +239,16 @@ struct to_device_type_impl {
  template <typename ValueType>
  struct to_device_type_impl<matrix::Dense<ValueType>*&> {
  + using type = matrix_accessor<device_type<ValueType>>;
  + static type map_to_device(matrix::Dense<ValueType>* mtx)
  + {
  + return to_device_type_impl<
  + matrix::Dense<ValueType>* const&>::map_to_device(mtx);
  + }
  +};
  +
  +template <typename ValueType>
  +struct to_device_type_impl<matrix::Dense<ValueType>* const&> {
  using type = matrix_accessor<device_type<ValueType>>;
  static type map_to_device(matrix::Dense<ValueType>* mtx)
  {
  