updated to d3v4, modern js, and prettier formatted
an iteration on Force-Directed SVG Icons from @syntagmatic
Replaces the circles in the force-directed graph with some SVG icons.
forked from micahstubbs's block: Force-Directed SVG Icons d3v4
https://cdnjs.cloudflare.com/ajax/libs/d3/4.13.0/d3.min.js