title: HighChart Shared Tooltip Number Formatting
body: <p>I'm using HighCharts JS for the very first time. So far, I'm very impressed. I'm charting multiples series and using a shared tooltip. The numbers in the shared tooltip are correct, but they are not formatted as I would like. For example, I'm seeing <code>9876</code> instead of <code>9,876</code>.</p>
  
  <p>I know that I can use the formatter to completely customize the tooltip. Instead of completely redoing the tooltip, I'd just like to format the number and keep the existing look and feel.</p>
  
  <p><strong>Question:</strong> Is is possible to specify a format for the number(s) in the tooltip without writing a custom formatter?</p>