add(examples) Interleaving deck.gl with MapboxOverlay

[chrisgervang]

For #8541

Background

We currently don't have a pure-js example for using MapboxOverlay with interleaved rendering. Let's add one.

Change List

• Add mapbox-overlay example to gallery

[Pessimistress]

I think we should just replace the existing mapbox-layer example with this one. The documentation currently recommends using MapOverlay over MapboxLayer as it offers more features.

[chrisgervang]

I think we should just replace the existing mapbox-layer example with this one. The documentation currently recommends using MapOverlay over MapboxLayer as it offers more features.

Hmm, it seems like we're all converging around the idea of removing MapboxLayer from the public api. v9 would be the best time to make a breaking change like that.

MapboxOverlay relies on it internally so I'd keep the implementation as-is, and just remove the export/docs/examples.

Alternately, formally deprecate and move an example to test/apps.

[coveralls]

coverage: 70.643%. remained the same
when pulling b8d2554 on chr/mapbox-overlay-interleave-example
into a5eccec on master.