Enable multi touch interaction for dataZoom in charts
http://echarts.apache.org/tutorial.html#Add%20interaction%20to%20the%20chart%20component mentions that we can enable an inside
slider so that you can use multi touch to zoom in/out of the chart (supposedly works on mobile as well).
We should add this to all our datazoom's by default so that the zooming functionality is more accessible to mobile devices or touch screens.