when using flyToNavigationState() - need to take care of some points

[hn-88]

1. Can't have camera keyframe and script keyframe with flyTo() in the same timestamp.
2. Need to enable openspace.setPropertyValueSingle("NavigationHandler.PathNavigator.IncludeRoll", true)
3. Also, our use case may look better with Settings > Navigation Handler > Path Navigator > Default path type Linear, which is set as openspace.setPropertyValueSingle("NavigationHandler.PathNavigator.DefaultPathType", 2.000000)
4. We could possibly work around this bug by saving multiple sequences and playing them one after another using javascript.
5. But other bugs like Camera path does not end when used in certain osrectxt OpenSpace/OpenSpace#3823 and flyToNavigationState with roll enabled and Linear paths sometimes jumps to new nav states OpenSpace/OpenSpace#3820 would need to be resolved first.

So, pausing development on this till those bugs are resolved. Will instead try ease-in/out by interpolating camera frames, using SLERP etc. https://medium.com/@akp83540/slerp-algorithm-a4ce1bacee4a