cesium-nodekit: support of self hosted Cesium ION ?

[remoe]

Does support cesium-nodekit a self hosted Cesium ION with asset id's? It needs accessToken per layer and a server configuration entry for the cesium api server in the earth file?

In CesiumJS (javascript) one can add it as follow:

const resource = await IonResource.fromAssetId(assetID, {
  accessToken: '<TOKEN>',
  server: 'https://example.ion'
});

const terrainProvider = CesiumTerrainProvider.fromUrl(resource);

[jasonbeverage]

We don't currently support self hosted Cesium Ion but we could. I've added an issue to track this at #2613 to track this.