add stacked bar functionality

[acolby]

It would be nice if one could easily create stacked bars as well as the default Chartjs charts.

If you add https://github.com/Regaddi/Chart.StackedBar.js as a dependency to this project and add the stacked bar directives as follows, it works great!

angles.directive('stackedbarchart', function () { return angles.chart('StackedBar'); });
angles.directive('stackedbar', function () { return angles.chart('StackedBar'); });

I can issue a pr that

• adds stacked bar as a dependency
• adds the stacked bar directives
• updates the readme accordingly

This is an excellent wrapper around chartjs and it would be nice to see it incorporate some of the open extensions. I can help!

let me know

[sebastialonso]

Did something happened with that PR? :)

[acolby]

lol, I didn't want to build it unless it was something you were interested in incorporating into the project. The stacked bar project would need to be a dependency and you may be trying to minimize dependencies.

Anyway, this was a while ago, but if it's something you're interesting in incorporating we can move forward with it.

Thanks for the project!