Simplify

I took a very simple approach to this. So far it has seemed to work out pretty well for me here: https://github.com/slamdata/slamdata. There's probably a whole slew of bugs in here waiting to come out, but I thought this might be a nice start for a rewrite.

Please review/comment/suggest.
`createClass` is too javascript-y. What about `defineComponent` or something like this. AFAIK React is moving away from `createClass` too in the future versions.