#14439 Create 2D intersection views for views in a grid ensemble

Rim2dIntersectionViewCollection::syncFromExistingIntersections() found the
intersections by walking the PDM child tree of the case. Views located in a
grid ensemble view collection or in the project level view collection are not
children of the case, so no 2D intersection view was created for their
intersections and "Show 2D Intersection View" did nothing.

Collect the intersections from the grid views displaying the case instead.

Display the 2D intersection views as a child of RimReservoirGridEnsemble, next
to the 3D views they are created from, and skip the node on the case to avoid
showing the same object twice in the project tree.

ApplicationLibCode/ProjectDataModel/RimReservoirGridEnsemble.h

@@ -123,6 +123,7 @@ public:
 protected:
     void appendMenuItems( caf::CmdFeatureMenuBuilder& menuBuilder ) const override;
     void defineUiOrdering( QString uiConfigName, caf::PdmUiOrdering& uiOrdering ) override;
+    void defineUiTreeOrdering( caf::PdmUiTreeOrdering& uiTreeOrdering, QString uiConfigName = "" ) override;
     void defineObjectEditorAttribute( QString uiConfigName, caf::PdmUiEditorAttribute* attribute ) override;
     void fieldChangedByUi( const caf::PdmFieldHandle* changedField, const QVariant& oldValue, const QVariant& newValue ) override;
     void createDerivedObjects() override;