message: code review: add a comment about Simplex_tree_boundary_simplex_iterator default ctor
diff: @@ -85,6 +85,7 @@ class Simplex_tree_boundary_simplex_iterator : public boost::iterator_facade<
  typedef typename SimplexTree::Vertex_handle Vertex_handle;
  typedef typename SimplexTree::Siblings Siblings;
  + // For cython purpose only. The object it initializes should be overwritten ASAP and never used before it is overwritten.
  Simplex_tree_boundary_simplex_iterator()
  : sib_(nullptr),
  st_(nullptr) {
  