Replace moment.js

[brdunfield]

moment is now in maintenance mode. We should consider porting to an active library.

https://momentjs.com/docs/

This will also cut down on the unneeded bloat in main.min.js that we have to manually discard every time we run npm run webpack

If we want to address this without removing moment entirely, we can look into using the following plugin to cut down on main.min.js bloat: https://www.npmjs.com/package/moment-locales-webpack-plugin