title: Google Combo Chart with multiple series, how to add custom HTML Tooltip
body: <p>I've Google combo chart and like to add a Tooltip.  The icCube documention has an example how to add a HTML tooltip but this will not work for series, only the last item in the serie gets the tooltip. I found an answer how to do this, see this <a href="https://stackoverflow.com/q/17924826/6825710">post</a>.</p>
  
  <p>But how can I achieve this in icCube?</p>