* Replace setCameraState with setNavigationState + equivalents
* Add documentation and verification of NavigationState-related interfaces
* Documentation and verification fixes
* Change reference frame behavior
* Scene fixes
* Replace earthrise recording with navigation state and time
* Fade fixes
* Clean up RenderableSphere. Add orientation properties.
* Sane defaults for Digital Universe
* Clean up New Horizons related code
* Add basic scene
* Add ability to initialize rotation as quaternion and mat3
* Adapt legacy code to new Renderable interface