Adds imbibition curves to relative permeability plot

Adds styling for imbibition relative permeability curves to the plot, differentiating them visually from drainage curves.

Adds UI elements (checkboxes) to control the visibility of drainage and imbibition curve sets. Also introduces a tracker that displays curve values near the cursor position.

ApplicationLibCode/UserInterface/RiuRelativePermeabilityPlotPanel.h

@@ -29,6 +29,7 @@
 
 class RiuDockedQwtPlot;
 class RiuRelativePermeabilityPlotUpdater;
+class RiuRelPermQwtPicker;
 class QButtonGroup;
 class QCheckBox;
 class QwtPlot;
@@ -107,6 +108,9 @@ private:
     std::vector<RigFlowDiagDefines::RelPermCurve> gatherUiSelectedCurves() const;
     QString                                       asciiDataForUiSelectedCurves() const;
 
+    const QwtPlotCurve* closestCurveSample( const QPoint& cursorPosition, int* closestSampleIndex ) const;
+    void                updateTrackerPlotMarkerAndLabelFromPicker();
+
     void contextMenuEvent( QContextMenuEvent* event ) override;
 
 private slots:
@@ -114,6 +118,8 @@ private slots:
     void slotSomeCheckBoxStateChanged( int );
     void slotCurrentPlotDataInTextDialog();
     void slotShowCurveSelectionWidgets( int state );
+    void slotPickerActivated( bool );
+    void slotPickerPointChanged( const QPoint& pt );
     void showEvent( QShowEvent* event ) override;
 
 private:
@@ -126,6 +132,14 @@ private:
     QPointer<RiuDockedQwtPlot>                    m_qwtPlot;
     std::vector<QwtPlotMarker*>                   m_myPlotMarkers;
 
+    QPointer<RiuRelPermQwtPicker> m_qwtPicker;
+    QString                       m_trackerLabel;
+    QwtPlotMarker*                m_trackerPlotMarker;
+
+    QGroupBox* m_curveSetGroupBox;
+    QCheckBox* m_showDrainageCheckBox;
+    QCheckBox* m_showImbibitionCheckBox;
+
     QGroupBox*    m_groupBox;
     QButtonGroup* m_selectedCurvesButtonGroup;
     QCheckBox*    m_showUnscaledCheckBox;