This is a simple example of a pluggable object simulator.  If you run the
SimulatorRunner file, it'll throw up a GUI file picker if a simulation class
isn't specified on the command line.  It will then:

* Run the simulation class's `start()` method,
* Call its `tick()` method,
* Call its `use()` method,
* then call its `stop()` method once `tick()` returns false.