ipywidgets

This folder is based off the the sample `web3` from https://github.com/jupyter-widgets/ipywidgets/blob/master/examples/web3

We have built a custom solution based on web3 sample to host ipywidgets outside of Jupyter Notebook.

IPywidgets traditionally use requirejs.
- traditionally as there seems to be some ongoing work to use commonjs2, though unsure how this will work with 3rd party widgets.
Using 3rd party widgets require:
- requirejs to be available in the current browser context (i.e. window)
- Base IPywidgets to be defined using define in requirejs.
Rather than bundling using amd or umd its easier to just import everything using commonjs2, then export for requirejs using define by hand.
- define('xyz', () => 'a') is a simple way of declaring a named xyz module with the value a (using requirejs).
- This is generally done using tools, however we'll hand craft this as it works better and easier.
- amd is not what we want, as out react ui doesn't use amd.
- umd is does not work as we have multiple entry points in webpack.
- Heres' the solution define('@jupyter-widgets/controls', () => widgets);