Add comment about rhumb lines being spirals for rhumb line intersection
Add comment about rhumb lines being spirals for rhumb line intersection

AnalyticalGraphicsInc/cesium,likangning93/cesium,jasonbeverage/cesium,CesiumGS/cesium,YonatanKra/cesium,YonatanKra/cesium,CesiumGS/cesium,YonatanKra/cesium,kaktus40/cesium,hodbauer/cesium,jasonbeverage/cesium,hodbauer/cesium,likangning93/cesium,CesiumGS/cesium,progsung/cesium,likangning93/cesium,progsung/cesium,geoscan/cesium,AnalyticalGraphicsInc/cesium,YonatanKra/cesium,CesiumGS/cesium,likangning93/cesium,CesiumGS/cesium,josh-bernstein/cesium,kaktus40/cesium,geoscan/cesium,josh-bernstein/cesium,likangning93/cesium,hodbauer/cesium