Support for copying GeoMech case settings using new input (#6471)

* Support copy and replace geomech case, to support importing another data file, but keep the view setup

* Make sure surfaces and intersections get updated with the correct separate result, too

* Simplify/refactor code

* Better naming

ApplicationCode/ProjectDataModel/RimGeoMechModels.h

@@ -38,7 +38,12 @@ public:
     RimGeoMechModels( void );
     ~RimGeoMechModels( void ) override;
 
-    caf::PdmChildArrayField<RimGeoMechCase*> cases;
+    RimGeoMechCase* copyCase( RimGeoMechCase* thecase, const QString& newInputFileName );
+    void            removeCase( RimGeoMechCase* thecase );
+    void            addCase( RimGeoMechCase* thecase );
+
+    std::vector<RimGeoMechCase*> cases() const;
 
 private:
+    caf::PdmChildArrayField<RimGeoMechCase*> m_cases;
 };