Extensible select and enumeration types

and their elements in schema LAYERED_2D_SHAPE_XIM taking into account BASED_ON types


 constructive_element_select - EXTENSIBLE GENERIC_ENTITY SELECT
          axis2_placement
          curve
          point_select
          surface

 external_identification_item - EXTENSIBLE GENERIC_ENTITY SELECT
          document_file
          file

 identification_item - EXTENSIBLE SELECT
          document_file
          shape_representation

 part_template_or_physical_unit_2d_shape_model_select - EXTENSIBLE GENERIC_ENTITY SELECT

 property_assignment_select - EXTENSIBLE SELECT
          characterized_object
          shape_element

 template_definition_select - EXTENSIBLE SELECT
          shape_representation

 versionable_item - EXTENSIBLE SELECT
          document_file
          shape_representation