message: Meritocracy: add +1 commerce for Watermill, Windmill
diff: <iYield>2</iYield>
  </ImprovementYields>
  </ImprovementYieldChange>
  + <ImprovementYieldChange>
  + <ImprovementType>IMPROVEMENT_WATERMILL</ImprovementType>
  + <ImprovementYields>
  + <iYield>0</iYield>
  + <iYield>0</iYield>
  + <iYield>1</iYield>
  + </ImprovementYields>
  + </ImprovementYieldChange>
  + <ImprovementYieldChange>
  + <ImprovementType>IMPROVEMENT_WINDMILL</ImprovementType>
  + <ImprovementYields>
  + <iYield>0</iYield>
  + <iYield>0</iYield>
  + <iYield>1</iYield>
  + </ImprovementYields>
  + </ImprovementYieldChange>
  </ImprovementYieldChanges>
  </CivicInfo>
  <CivicInfo>
  