Extensible select and enumeration types

and their elements in schema RISK_SCHEMA taking into account BASED_ON types


 probable_item - EXTENSIBLE SELECT

 risk_communication_select - EXTENSIBLE SELECT
          lessons_learned
          risk
          risk_analysis
          risk_assessment
          risk_consequence
          risk_context
          risk_control
          risk_estimation
          risk_evaluation
          risk_identification
          risk_impact_assignment
          risk_perception
          risk_perception_context
          risk_perception_relationship
          risk_probability
          risk_probability_assignment
          risk_reduction
          risk_relationship
          risk_resource
          risk_treatment

 risk_impact_item - EXTENSIBLE SELECT

 risk_source_item - EXTENSIBLE SELECT