Add support for grid calculations as data source for statistics

- add data source selection, either Case Property or Grid Calculation
- add Time Step Selection, can be used for both dynamic case properties and Grid Calculations
- optionally release grid calculation data when statistics is computed
- recursive grid calculations is supported

ApplicationLibCode/ProjectDataModel/RimIdenticalGridCaseGroup.cpp

@@ -433,6 +433,7 @@ RimEclipseStatisticsCase* RimIdenticalGridCaseGroup::createStatisticsCase( bool
 
     newStatisticsCase->openEclipseGridFile();
     newStatisticsCase->eclipseCaseData()->computeActiveCellBoundingBoxes();
+    newStatisticsCase->selectAllTimeSteps();
 
     return newStatisticsCase;
 }