Easy to break camera in Columbus View

[mramato]

1. Run Cesium Viewer
2. Switch to Columbus View
3. Zoom out with the wheel (until the map is completely gone)
4. Hit home button.

At this point, home won't fly you home, it takes you somewhere else instead. I think there are some other issues as well. Hitting home multiple times doesn't help, it always takes you back to the wrong location until you switch modes and switch back.

CC @bagnell