Highlight the curve belonging to the legend you click on. (#9259)

* Highlight the curve belonging to the legend you click on.
* Make sure legend curve order remains the same when changing hilited curve

ApplicationLibCode/ProjectDataModel/Summary/RimSummaryPlot.h

@@ -252,6 +252,7 @@ protected:
 
 private slots:
     void onPlotZoomed();
+    void updateCurveOrder();
 
 private:
     std::vector<RimSummaryCurve*>         visibleSummaryCurvesForAxis( RiuPlotAxis plotAxis ) const;