District Instance
list: Return all districts, which can filter ballot items.
retrieve: Return a specific district, which can filter ballot items.
GET /api/districts/3616/?format=api
http://michiganelections.io/api/districts/3616/?format=api", "id": 3616, "category": "County Commissioner District", "name": "Saginaw County, 1st District" }{ "url": "