message: code review: Add short cut for contiguous vertices increment
diff: @@ -251,6 +251,21 @@ class Simplex_tree_boundary_opposite_vertex_simplex_iterator : public boost::ite
  Siblings * for_sib = sib_;
  Siblings * new_sib = sib_->oncles();
  auto rit = suffix_.rbegin();
  + if (SimplexTree::Options::contiguous_vertices && new_sib == nullptr) {
  + // We reached the root, use a short-cut to find a vertex.
  + if (rit == suffix_.rend()) {
  + baov_.second = baov_.first->first;
  + // Segment, this vertex is the last boundary simplex
  + baov_.first = for_sib->members_.begin()+last_;
  + sib_ = nullptr;
  + return;
  + } else {
  + // Dim >= 2, initial step of the descent
  + baov_.first = for_sib->members_.begin()+*rit;
  + for_sib = baov_.first->second.children();
  + ++rit;
  + }
  + }
  for (; rit != suffix_.rend(); ++rit) {
  baov_.first = for_sib->find(*rit);
  for_sib = baov_.first->second.children();
  