[API]: Watersheds Seed Data

[brettpalmberg]

The /locations API can now support any geojson geometry in the geometry field (not limited to a point). This opens the possibility of storing known watershed boundaries as locations (usgs-huc boundaries, as well as cwms-watershed extents currently stored in github.com/USACE/cumulus-api).

Recommend we load existing cumulus watersheds (excluding any district, division, or River Forecast Center (RFC) boundaries) as seed data into the location table.

Note: office boundaries or RFC boundaries may be added as a different datatype at a later time.