Use React packages from NPM

See https://github.com/facebook/react/pull/5381

Need to have a bundle like this:

```
global.React = require('react');
global.ReactDOM = require('react/lib/ReactDOM');
global.ReactDOMServer = require('react/lib/ReactDOMServer');
```

And Webpack it to produce the `react.js` file that should be loaded by ReactJS.NET
