Feature: add collection render layers to map in HTML collection view

[hrodmn]

This does two things:

• adds links to the /WebMercatorQuad/tilejson.json and WebMercatorQuad/tilejson.json endpoints to the /collections/{collection_id} STAC json response for any available renders extension entries
  • this is nice for because STAC browser will display the links for easy access to the visualizations
  • I think it is a little messy because map and tilejson are not true rel types 🤷
• loads any tilejson layers into the map view in the collection HTML response in the STAC API
  • and adds full screen button

[vincentsarago]

😍