Consider updating to d3.v4

[cyremur]

I am using in this for a personal project in conjunction with typescript and d3.v4. I had to make some changes, mainly to incorporate the different naming convention used in v4. If you like, I could PR these updates back to your gantt-chart.

If you decide this is a valuable addition to your repo, please tell me how you would like to incorporate the changes (updating the old file, inserting a separate file for v4, etc.).

[SOSharkie]

@cyremur I am trying to incorporate this Gantt chart into a project with typescript as well, and I'm interested in how you achieved this, would you mind sharing?

[cyremur]

@SOSharkie Have a look at this project: https://github.com/cyremur/InDiFront

I've rewritten the gantt js code in gantt-chart-d3.ts. Note that although it is working, it's not a perfect adaptation to typescript and probably breaks quite a few best practices I wasn't aware of since I only just started using typescript. Should give you a somewhat better starting point, though. You can also look at index.ts for some example code how to use the gantt-chart.