Hapi mode

This pull request replaces `Express` with `Hapi` for the main application server. It sets up a proxy to `webpack-dev-server` so that assets have access to features such as hot module replacement.

Additionally, I changed the way actions are accessed, following some interview material with Facebook staff working on their flux apps.
Would this 404 if the path were localhost:4000/people/1 and served via server-side rendering?