Add a new layer to the map for "Organizational Members"

[exoticDFT]

We'll be piloting a organizational membership over the next year+. One perk will be to add a pin to the map to mention them, similar to the regional groups layer. The PR that handled this can be found at #102.

[exoticDFT]

Do we want to have a difference between the "founding" members and the future organizational members?

What other questions do we need to consider about this?