Set ToolTip

Author: niels9001

components/RadialGauge/src/RadialGauge.cs

@@ -244,6 +244,7 @@ private static void OnValueChanged(DependencyObject d)
                 {
                     valueText.Text = radialGauge.Value.ToString(radialGauge.ValueStringFormat);
                 }
+                ToolTipService.SetToolTip(radialGauge, radialGauge.Value);
             }
         }
     }