title: XYTextAnnotation in DynamicTimeSeriesCollection
body: <p>I'm trying to implement XYTextAnnotation in DynamicTimeSeriesCollection. 
  I have no idea how to find X value of series in DynamicTimeSeriesCollection. My code so far:</p>
  
  <pre><code>DynamicTimeSeriesCollection dataset = new DynamicTimeSeriesCollection(1, 60, new Minute());
  final JFreeChart result = ChartFactory.createTimeSeriesChart(TITLE, "A", "B", dataset, true, true, false);
  float[] series1Small = new float[10];
  dataset.setTimeBase(new Minute(1, 1, 1, 1, 2013));
  dataset.addSeries(series1Small,0,"1");
  JFreeChart result = ChartFactory.createTimeSeriesChart(TITLE, "Время", "Платежи", dataset, true, true, false);
  final XYPlot plot = result.getXYPlot();
  -----------------------------------------------------------Below line doesn't work. 
  
  TimeSeriesDataItem item1 = series1.getDataItem(series1.getItemCount() - 1);
  createAnnotation(item1,plot);
  </code></pre>
  
  <p>This is a function that used to work for annotation with TimeSeriesCollection. </p>
  
  <pre><code> public static void createAnnotation(TimeSeriesDataItem item,XYPlot plot)
  {
     double xAnnotation = item.getPeriod().getFirstMillisecond();
     double yAnnotation = item.getValue().doubleValue();
     XYTextAnnotation annotation = new XYTextAnnotation(item.getValue().toString(), xAnnotation, yAnnotation);
     annotation.setFont(new Font("Arial",Font.BOLD,11));
     plot.addAnnotation(annotation);
  }
  </code></pre>