Add Total option to be displayed with the relevant charts
Boolean option to display the total in the chart
See http://jsfiddle.net/highcharts/tnSRA/ for an implementation of pie title, where the total can be entered as a variable.
For example, in Donut or Pie to display the Total of all the groups in the center of the chart.
The total of what? All the points in the chart? We do have options to show the total of a stack in stacked charts.