Extensible select and enumeration types

and their elements in schema PROJECT_MIM taking into account BASED_ON types


 characterized_product_definition - EXTENSIBLE SELECT
          product_definition
          product_definition_relationship

 date_and_time_item - EXTENSIBLE SELECT
          event_occurrence
          organizational_project

 date_item - EXTENSIBLE SELECT
          event_occurrence
          organizational_project

 event_occurrence_item - EXTENSIBLE GENERIC_ENTITY SELECT
          organizational_project

 project_item - EXTENSIBLE SELECT