Clean up & improve the word cloud code

[rikai]

The word cloud code mostly works but needs some cleanup and performance improvments so it's not bogging down the bot's other tasks.

Then after that is done, it will need UI hooks.

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[rikai]

D3.js is what most of the word cloud code is based on, is a large part of what our Code Climate issues come from and has been updated significantly since it was pulled in.

We should at the very least update it and fix any breakages, at minimum.

[rikai]

D3-Cloud has also been updated and is used in our code as well. 👍