RicImportGridAndSummaryEnsembleFeature: Add feature for importing grid and summary ensembles

- Add RicImportGridAndSummaryEnsembleFeature with icon and menu/toolbar registration
- Register in main window toolbar, import menu (both windows)
- Add feature to plot window Standard toolbar
- Wire up post-import view and plot creation
- Skip grid/summary ensemble creation when no files of that type are found
- Keep focus in plot window when no grid ensembles are created

ApplicationLibCode/ProjectDataModel/EnsembleFileSet/RimEnsembleFileSetTools.cpp

@@ -103,6 +103,7 @@ std::vector<RimReservoirGridEnsemble*> createGridEnsemblesFromFileSets( const st
         project->assignIdToCaseGroup( ensemble );
         eclipseCaseColl->reservoirGridEnsembles.push_back( ensemble );
 
+        ensemble->createGridCasesFromEnsembleFileSet();
         ensemble->loadDataAndUpdate();
         ensembles.push_back( ensemble );
     }