message: copy geomodel using GeoModelBuilderCopy
diff: @@ -230,12 +230,12 @@ namespace RINGMesh {
  class RINGMESH_API GeoModelBuilderCopy {
  ringmesh_disable_copy( GeoModelBuilderCopy ) ;
  friend class GeoModelBuilder ;
  + public:
  + void copy_geomodel( const GeoModel& from ) ;
  private:
  GeoModelBuilderCopy( GeoModelBuilder& builder, GeoModel& geomodel ) ;
  - void copy_geomodel( const GeoModel& from ) ;
  -
  private:
  GeoModelBuilder& builder_ ;
  GeoModel& geomodel_ ;
  