title: How to do a timeline of layers using cesium?
body: <p>I would like to do a kind of animation using cesium. How do you think is the best way to send getMap request (maybe using webMapServiceImageryProvider) and save the result to later display each layer in time ?
  I was thinking to use WMSImageryProvider to create image of each layer and then, save them in viewer.imageryLayers.newMap, then loop on this new map to display layers.</p>
  <p>To illustrate :
  My layer named meteo has a period dimension (january, february...) throw a year.
  I want to send a getMap request for dimension january, then february, then march... And after loading all of them, display one each second probably on the map to see an evolution.</p>
  <p>For the moment, I got a panel with a button. I want my app to load this content when i click. But i do not understand for the moment how to send getMap request and save result in a map or something equal.</p>
  <p>If any of you has an idea.</p>