First attempt to add highcharts to graphing backends.
This backend supports line, area, stacked area and spline.
(Should work with other types, but I don't think that's revelant for graphite usage)
Highcharts seems to crash when there is a large amount of data in area mode.
Add support for highcharts-more and highcharts exporting.
Implement chart onclick redirect to inspect page of graph-explorer
Match example file with other example: replace localhost:8000 with <graphite hostname:port>
Fix series name callback when no callback is specified.
Workaround for a graphite but not working properly with object {x, y}
Remove useless graphing options (area without stack, splines, ..)
Add highcharts to the README.md documentation
Permit the usage of HTML in yAxis and legend to match flot rendering
tiny cleanup
allow caller to set xaxis/yaxis options