Rename `redux.js` to `index.js`.

Move the Esprima based module into place.

Closes #51.
Remove `esprima.t.js`.

No need to test Esprima itself any longer. I've got a feel for how it
works.

Closes #52.
Export named functions.

Rewrote the generator to detect assignments to the `exports` function.
It was so easy I see that I could support both `exports` and
`module.exports`.

Closes #53.