Yoichi Hirai - 2013-06-11

I just implemented grouping containers on top of js-graph.it.
When a content moves, the container expands and shrinks accordingly.
demo: https://yoichihirai.com/js-graph-it-with-containers/homepage/index.html

It is a quick hack and the code is untested.
zenluca's clean code helped me a lot.