message: Center captions displayed on empty timeline view (win)
diff: </Popup>
  </Grid>
  </ScrollViewer>
  - </Grid>
  - <TextBlock Text="No entries here... Go ahead and track some time!" Width="125" HorizontalAlignment="Center"
  - VerticalAlignment="Center" TextWrapping="Wrap" TextAlignment="Center" Margin="0 100 0 0"
  + <TextBlock Grid.Row="3" Grid.Column="1" Text="No entries here... Go ahead and track some time!" Width="125" HorizontalAlignment="Center"
  + VerticalAlignment="Center" TextWrapping="Wrap" TextAlignment="Center"
  Visibility="{Binding TimeEntryBlocks, Converter={StaticResource EmptyListToVisibleConverter}}"
  MouseWheel="HandleScrollViewerMouseWheel"/>
  - <TextBlock Text="No activity was recorded yet..." HorizontalAlignment="Right"
  - VerticalAlignment="Center" TextAlignment="Center" Margin="0 100 10 0"
  + <TextBlock Grid.Row="3" Grid.Column="2" Text="No activity was recorded yet..." HorizontalAlignment="Center"
  + VerticalAlignment="Center" TextAlignment="Center"
  Visibility="{Binding ActivityBlocks, Converter={StaticResource EmptyListToVisibleConverter}}"
  MouseWheel="HandleScrollViewerMouseWheel">
  <TextBlock.LayoutTransform>
  </TextBlock.LayoutTransform>
  </TextBlock>
  </Grid>
  + </Grid>
  </UserControl>
  