Fix bugs in bisector window, add bus number as a bisecting option,

allow upper/lower radio buttons to switch text for more clarify as to
what they do.

bisectwindow.h

@@ -30,6 +30,7 @@ private slots:
     void updatePercentSlider();
     void updateFrameNumText();
     void updatePercentText();
+    void updateSectionsText();
 
 private:
     Ui::BisectWindow *ui;