Migrate example to be compatible with Express 4.x

I tried to make minimal changes to the example to let it run with Express 4.

I'm not an experienced Express developer and did mostly the steps from the [upgrade guide](https://github.com/strongloop/express/wiki/Migrating-from-3.x-to-4.x).

Currently all packages are bound to depend on version `">= 0.0.0"`. I think that binding them to a more specific version could help in case of future updates. What do you think? If you agree I'd like to fix the current known working versions of each package.