Add a `package.json` file, publish to npm

I've [published this component to npm](https://www.npmjs.org/package/dom-support) and added `timoxley` as an owner. It now works with browserify.

Also now using `ded/domready` because it's the same version that's published to the npm registry, so for consistency.

If you wouldn't mind merging the package.json file then I won't need to maintain my fork.

Cheers!