Proof of concept for a webapplication where POSTed JSON payloads are converted to a RX Observable
to which handler services can subscribe.
To run use Gradle: gradle clean bootRun in the root of the project; the application will start on port 8080.
To upload example payload threeitems.json using HTTPie: http POST localhost:8080/command < threeitems.json, the
example observer should log the command it just saw.
The SlowObserver class demonstrates observing on a different thread; when a command package is uploaded, the POST
will return immediately, even though the SlowObserver takes a few seconds to complete its processing.