Add snippets for all Layer classes

[hhkaos]

Today the extension contain just a one snippets

Snippet	Description
addLayerFromPortalItem	Add a new layer to the map from an ArcGIS Online or Enterprise portal item. Contains a placeholder for the portal item id.

But there are a lot of (Layer) types.

It would be nice to have snippets for the following classes: (38 in total)

• Vector layers
  • CSVLayer
  • GeoJSONLayer
  • GeoRSSLayer (OGC)
  • GraphicsLayer
  • FeatureLayer
  • FeatureLayer (client-side)
  • MapNotesLayer
  • OGCFeatureLayer OGC API - Features
  • RouteLayer
  • StreamLayer
  • VectorTileLayer
  • WFSLayer OGC Web Feature Service (WFS)
• Raster Layers
  • ImageryTileLayer
  • ImageryLayer
  • ImageryTileLayer /w COG
  • ImageryTileLayer (Multidimensional)
  • WebTileLayer - (XYZ layer / Slippy maps)
  • WMSLayer OGC Web Map Service (WMS)
  • WMTSLayer OGC Web Map Tile Service (WMTS)
  • WCSLayer OGC Web Coverage Service (WCS)
  • MapImageLayer (Time-based) Traffic layer
  • BingMapsLayer
  • OpenStreetMapLayer
• 3D layers
  • SceneLayer
  • Elevation
  • PointCloud
  • BuildingSceneLayer
  • LineOfSightLayer
  • DimensionLayer
  • IntegratedMeshLayer
  • VoxelLayer
• Others
  • MediaLayers (Overlayed images with control points)
  • MediaLayers (/w video)
  • KML Layer (OGC)
  • GroupLayer
  • SubtypeGroupLayer
  • TileLayer
  • KnowledgeGraphLayer

Most of these layers have the possibility to be initialized in different ways (e.g. using source or a similar property), with a url, and/or using a portalItem. Like FeatureLayer (using: source, url, portalItem), RouteLayer (using: stops, url and portalItem, StreamLayer (webSocketUrl or url), etc.

I think the portalItem is the easiest to remember, and having addLayerFromPortalItem I don't see that very relevant. I also think using the URL is probably one of the most commons ways, but also the easiest to remember. I would say having the custom-source/client-side (for been the most complex to remember) or both (including url) if you think that should be default, would be my preference for these snippets.

Does it make sense @kellyhutchins ? // cc: @RalucaNicola

[kellyhutchins]

Sounds great.