Added Clear Screen button to clear LOG text box

MainPage.xaml

@@ -27,5 +27,6 @@
 
         <TextBox x:Name="txtOut" TextWrapping="Wrap" Text="" Margin="10,197,10,10" IsReadOnly="True" ScrollViewer.HorizontalScrollBarVisibility="Disabled" ScrollViewer.VerticalScrollBarVisibility="Visible" ScrollViewer.VerticalScrollMode="Enabled" Background="{x:Null}" IsTapEnabled="False" IsRightTapEnabled="False" IsHoldingEnabled="False" IsDoubleTapEnabled="False" ManipulationMode="None"/>
         <Button x:Name="bRdCardID" Content="Get Card ID" HorizontalAlignment="Left" Margin="180,120,0,0" VerticalAlignment="Top" Width="140" Click="bRdCardID_Click"/>
+        <Button x:Name="bClearLog" Content="Clear Screen" HorizontalAlignment="Left" Margin="180,160,0,0" VerticalAlignment="Top" Width="140" Click="bClearLog_Click"/>
     </Grid>
 </Page>

MainPage.xaml.cs

@@ -118,5 +118,10 @@ namespace Test_uFCoder_lib
                 prnl(s);
             }
         }
+
+        private void bClearLog_Click(object sender, RoutedEventArgs e)
+        {
+            txtOut.Text = String.Empty;
+        }
     }
 }