Update d3 dependencies to version 3

[ahmohamed]

This PR updates outdated dependencies d3-array, d3-selection and d3-transition as well as other D3-* packages to version 3. The only incompatibility was the removal of d3 event. Relevant code was updated to use the new syntax.
Fixes #85

[Felix83000]

Hi,

All d3-color < 3.1.0 are vulnerable to a Regular expression Denial of Service. This issue has been patched in version 3.1.0. There are no known workarounds for previous versions.

Can you use this PR to push a new version of react-wordcloud?

If not I will stop using react-worldcloud as it becomes vulnerable....

Thanks for your help

[Felix83000]

To fix d3-color vulnerabilitie, please use last version of
d3-scale
d3-scale-chromatic
d3-transition

[Felix83000]

[ahmohamed]

I'm not a maintainer of this package and don't have write access to this repo. The maintainer @chrisrzhou hasn't been responsive either. Personally I've been using my own fork directly. If @chrisrzhou wants to archive this repo, I'm happy to create another npm package with these updates (say react-wordcloud2).