remove todo

There will not be any crash as the value for new vertices
is always set. However with Polyhedron since we don't reuse
vertices, the map size might get large. Surface_mesh is fine

Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/Adaptive_sizing_field.h

@@ -145,7 +145,6 @@ class Adaptive_sizing_field
   void calc_sizing_map(FaceGraph& face_graph
                      , const NamedParameters& np)
   {
-    //todo ip: please check if this is good enough to store curvature
     typedef Principal_curvatures_and_directions<K> Principal_curvatures;
     typedef typename CGAL::dynamic_vertex_property_t<Principal_curvatures> Vertex_curvature_tag;
     typedef typename boost::property_map<FaceGraph,