function KmlCamera(position, headingPitchRoll) {
  this.position = position;
  this.headingPitchRoll = headingPitchRoll;
}
Representation of <Camera> from KML
@alias KmlCamera
@constructor

@param {Cartesian3} position camera position
@param {HeadingPitchRoll} headingPitchRoll camera orientation