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/RimGeoMechCase.h

@@ -72,6 +72,8 @@ public:
 
     CaseOpenStatus openGeoMechCase( std::string* errorMessage );
 
+    RimGeoMechCase* createCopy( const QString& newInputFileName );
+
     RigGeoMechCaseData*       geoMechData();
     const RigGeoMechCaseData* geoMechData() const;