responsive/Update/Retina
responsive/Update/Retina

the code for the "responsive" option has been rewritten (less bugs);
an function to update the graph is now available (updateChart - see https://github.com/FVANCOP/ChartNew.js/wiki/180_Update_Chart)
The responsive option works now for retina display.
FVANCOP/ChartNew.js,Kosmas/ChartNew.js,Kosmas/ChartNew.js,FVANCOP/ChartNew.js