title: How do I selecting a date range (like onClick but drag/select)
body: <p>I'd like to rewrite <a href="http://vizwit.io" rel="noreferrer">vizwit</a> using Chart.js, and I'm having a hard time figuring out how to get the date/time chart interaction to work. If you try selecting a date range on <a href="http://vizw.it/?gist=51db593dc0537d1a3f05" rel="noreferrer">this demo</a>, you'll see that it filters the other charts. How do I get Chart.js to let me select a range like that on its time scale chart? It seems like by default it only lets me click on a specific date point.</p>
  
  <p>Thanks for your time.</p>