* Add a camera path topic and compute remaining time in path
* Remove unused parameter in function
* Include speed scale in estimation of time the path will take
* Includes cleanup and address review comments
* Round instead of ceil, to make countdown reach 0 in most cases
* Update GUI hash
* Use linear camera path when within target bounding sphere
And do a workaround for speed computation when bounding spheres are large
Closes#1910 (by at least making it so that the camera moves in an observable speed)
* Make linear paths rotate based on time rather than distance (closes#1947)
* Change spline curve parameter interval from [0,1] to [0,nSegments], for slightly increased precision
* Use linear paths whenever precision isn't enough/paths are too long (and traverse linear paths differently, to make them less depending on the distance)
* Remove OrbitalNavigator.LinearFlight and instead add "Zoom to" helper functions (closes#1837 )
* Add check to prevent triggering awkward short paths, for example when flying to the current target or to the same geo position twice
* Refactor speed code and handle speed when path is shorter than start+closeup distance
* Add easing to speed dampening
* Add topic for engine mode (to be used for UI later)
* Cleaner log when creating paths (some previous info messages are now debug messages)
Related PR: OpenSpace/OpenSpace-WebGuiFrontend#70
Same path as AvoidCollision, but with lookat rotation instead of slerp. Useful (needed) for some cases in the interactive installations, but should be replaced later on as it leads to fast rotations
