A copy of #9 with some corrections and me being opinionated

[ayroblu]

Hi,

I wanted to use this package, it looked a little out of date so I quickly did up a few changes to make it look better in my linter. Its a copy of some of pyramation's stuff, but fixed. Added a linter, added a test (with the front page's example in it)

Don't merge this in this state obviously, but it if you ask nicely I can undo some of my changes to be similar to your style (I couldn't get prepublish working with git-urls). I use 2 spaces and no semi colons, that's why there's so many changes. Appreciate your package! I could not figure out how MathJax could work with React until this!

yarn lint
yarn test