* check TODO file in include/CGAL
- restore the changes in the examples directory (example3.C and example4.C)
- update doc for vertex base and face base when the new design arrives
- check the typedefs.h file in the demo directory to make sure that
  definitions make sense
- add in user manual geometric interpretation in terms of cones in 3D; see
  corresponding emails
- add section about dimension of Apollonius_graph_2 in user manual
- in the reference manual:
     "Gt" => "ApolloniusGraphTraits_2"
     "Agds" and "ApolloniusGraphDataStructure_2" => "ApolloniusGraphDS_2"
- "CGAL::Apollonius_graph_data_structure_2<Vb, Fb>" : replace
  Vb/Fb by the concept names ApolloniusGraphVertexBase_2/...
  Similarly in references to it, where you could also don't put anything,
  i.e. just "CGAL::Apollonius_graph_data_structure_2" (?).
- "number_of_hidden_weighted_points()" in vertex base should return size_t;
  also add this in the spec.
- see email to cgal-editor with answers to Sylvain's questions
- ask Mariette to add access functions to the TDS of Triangulation_2.
- add a short names files and include it in all header files (to
  please the VC7 compiler)