Upgrade stomp-websocket version and connect call

This commit:
* upgrades stomp-websocket to v2.3.0
* changes the `stomp.connect('login','pass',callback)` call to a
 `stomp.connect({},callback)` since broker credentials aren't
 required here.
* moves resources to `src/main/resources` in the initial project, as
 mentioned in the actual guide.