title: C3js stacked bar chart with multiple pieces of data for each bar section
body: <p>I'm trying to create a stacked bar chart where each bar section in a group will have two pieces of data, a count and a cost. I want the count to be reflected in the bar, and I want the cost to be displayed in the bar label.</p>
  
  <p>I'd also like to be able to display both the count and the cost in the tooltip.</p>
  
  <p>Is this possible, and what is the easiest way to do it?</p>