Extensible select and enumeration types

and their elements in schema SURFACE_CONDITIONS_MIM taking into account BASED_ON types


 document_reference_item - EXTENSIBLE SELECT
          dimensional_size
          externally_defined_dimension_definition

 external_identification_item - EXTENSIBLE GENERIC_ENTITY SELECT
          document_file
          product_definition
          trimmed_curve

 identification_item - EXTENSIBLE SELECT
          dimensional_size
          document_file
          shape_representation

 versionable_item - EXTENSIBLE SELECT
          document_file
          shape_representation