added oculus rift support and first person controls

Implements feature request https://github.com/robhawkes/vizicities/issues/57
Depends on [Oculus Bridge](https://github.com/Instrument/oculus-bridge) and Three.js [OculusRiftEffect](https://github.com/mrdoob/three.js/blob/master/examples/js/effects/OculusRiftEffect.js)
Also added first person controls using arrow keys.