title: How to preserve dates from xts time series data after forecasting
body: <p>Please consider this small dataset:    </p>
  
  <pre><code>library(xts)
  library(ggplot2)
  library(forecast)
  
  data &lt;- data.frame(idDate = c("12-12-2012", "13-12-2012", "14-12-2012", "16-12-2012", "19-12-2012"), score= c(110, 120, 130, 200, 180))
  date &lt;- as.Date(as.character(data$idDate), "%d-%m-%Y")
  score &lt;- as.numeric(data$score)
  
  myxts &lt;- xts(score, date)
  autoplot(myxts)
  </code></pre>
  
  <p>So far the date (Index) along the x axis is preserved but as soon as I call forecast, the date along my x axis gets converted to integer. see below:</p>
  
  <pre><code>d.arima &lt;- auto.arima(myxts)
  d.forecast &lt;- forecast(d.arima, level = c(95), h = 3)
  d.forecast
  autoplot(d.forecast)
  </code></pre>
  
  <p>questions: 
  How can the index from <code>myxts</code> be kept? 
  Is there a way to tell <code>forecast</code> or <code>auto.arima</code> to preserve the date (Index) from <code>myxts</code>?</p>