[BUG] Doughnut Chart: Legend ‘left’ and ‘right’ not possible

Hi,

I created an example with a simple Doughnut chart and tried to position the legend on the right side.
In the documentation (http://www.chartjs.org/docs/#chart-configuration-legend-configuration) I saw the possible values ‘top’, ‘right’, ‘bottom’ and ‘left’.

If I use the property “legend.position”, only ‘top’ and ‘bottom’ work fine.
If I use ‘left’ or ‘right’ instead, there is an error “Cannot read “0” of undefined”:

https://jsfiddle.net/3pku19sj/

Kind Regards,
Eraser