working KML gx:Tour demo


I'd like to announce a working KML gx:Tour demo for Cesium. Please

look at a sample here:
this is a tour of a flight taken from Zurich Kloten airport above
the Swiss Alps to Zermatt, and then landing at Locarno. You can use
the timeline controls on the bottom of the page to control the tour.
as a comparison, a video of the same flight is here:
the code is in our repository, currently in this changeset:
what works: