title: Creating a stacked columnchart (Visualisation API)
body: <p>I wish to create a stacked column chart, and isStacked(true) is only half the story. How do I make the columns "stacked"? eg: I have a bar of countries, and each bar is divided into the number of industries it has.</p>
  
  <p>I looked at all the AbstractDataType options, but wasnt able to find anything. What am I missing?</p>
  
  <p>Thanks.</p>