message: Remove old GEO::index_t
diff: @@ -303,7 +303,7 @@ namespace RINGMesh {
  surface_style_.vertex_color_.Value.z );
  }
  if( selected_entity_type_ == 0 ) {
  - for( GEO::index_t s = 0; s < GM_.nb_surfaces(); s++ ) {
  + for( index_t s = 0; s < GM_.nb_surfaces(); s++ ) {
  if( GM_.surface( s ).is_on_voi() ) {
  GM_gfx_.surfaces.set_surface_visibility( s, show_voi_ );
  }
  @@ -737,7 +737,7 @@ namespace RINGMesh {
  {
  colored_cells_.new_status = false;
  show_colored_layers_.new_status = false;
  - for( GEO::index_t r = 0; r < GM_.nb_regions(); r++ ) {
  + for( index_t r = 0; r < GM_.nb_regions(); r++ ) {
  GM_gfx_.regions.set_region_color( r,
  std::fmod( GEO::Numeric::random_float32(), 1.f ),
  std::fmod( GEO::Numeric::random_float32(), 1.f ),
  @@ -756,7 +756,7 @@ namespace RINGMesh {
  }
  colored_cells_.new_status = false;
  show_colored_regions_.new_status = false;
  - for( GEO::index_t l = 0;
  + for( index_t l = 0;
  l < GM_.nb_geological_entities( Layer< 3 >::type_name_static() ); l++ ) {
  float red = std::fmod( GEO::Numeric::random_float32(), 1.f );
  float green = std::fmod( GEO::Numeric::random_float32(), 1.f );
  