title: Chartist: want to either click or hover on a bar chart to bring up tooltip
body: <p>Using the chartist tooltip plugin on a bar chart, I implemented a tooltip that comes up when the mouse cursor hovers over a bar, displaying the value of the bar plus other information. This works great. However, I'd like for this to work similarly when the user taps or clicks the bar, for touch-screen devices that don't support a mouse.</p>
  <p>Ideal behavior would be for the tooltip to disappear when the user lifts the finger from the screen, or releases the mouse-click, similar to a &quot;momentary contact&quot; physical button or switch. However, what happens with the current hover implementation is that the tooltip remains displayed until an empty area of the chart is tapped or clicked.</p>
  <p>How do I make the tap or mouse-click &quot;momentary contact&quot; without sacrificing the hover behavior?</p>