Conditional Rendering (Stage 1)

[ingalls]

Context

Our last big update was diff based rendering which sped up rendering tremendously as only features that came through the socket would be upserted. This is great until you run into a layer like the lightening layer where large numbers of essentially unchanging features come through the socket and are rendered.

This PR introduces the following:

• Introduces a COT class that implements the Feature type and serves as a container for helper fns
• Introduces an as_rendered() fn which only builds a feature with the minimum properties needed to render it on the map

TODO:

• MultiSelect doesn't differentiate between COT and Feat

Ref: #264