message: improve Dense documentation
diff: @@ -471,7 +471,8 @@ Dense<ValueType>& Dense<ValueType>::operator=(const Dense& other)
  this->values_.resize_and_reset(this->get_size()[0] * this->stride_);
  }
  // we need to create a executor-local clone of the target data, that
  - // will be copied back later.
  + // will be copied back later. Need temporary_clone, not
  + // temporary_output_clone to avoid overwriting padding
  auto exec = other.get_executor();
  auto exec_values_array = make_temporary_clone(exec, &this->values_);
  // create a (value, not pointer to avoid allocation overhead) view
  