Graphing window now retains your current view when graphs are added and subtracted unless you get down to no graphs.

This makes it easier to load lots of graphs and do work without having the graph constantly resize.

graphingwindow.h

@@ -55,6 +55,7 @@ private:
     QVector<CANFrame> *modelFrames;
     QList<GraphParams> graphParams;
     QPen selectedPen;
+    bool needScaleSetup; //do we need to set x,y graphing extents?s
 
     void showParamsDialog(int idx);
 };