Extensible select and enumeration types

and their elements in schema Appearance_assignment_arm taking into account BASED_ON types


 appearance_context - EXTENSIBLE GENERIC_ENTITY SELECT
          Representation

 appearance_select - EXTENSIBLE GENERIC_ENTITY SELECT

 identification_item - EXTENSIBLE SELECT

 measure_value - EXTENSIBLE SELECT
          any_number_value
          any_string_value
          length_measure
          plane_angle_measure

 overriding_style_context - EXTENSIBLE GENERIC_ENTITY SELECT
          Detailed_geometric_model_element
          Styled_model

 presented_model_select - EXTENSIBLE GENERIC_ENTITY SELECT
          Styled_model