feed auth can require registering an IP address with a transit agency

[drewda]

For example:

    {
      "id": "f-foothilltransit~rt",
      "spec": "gtfs-rt",
      "urls": {
        "realtime_vehicle_positions": "https://foothilltransit.rideralerts.com/myStop/GTFS-Realtime.ashx?Type=VehiclePosition",
        "realtime_trip_updates": "https://foothilltransit.rideralerts.com/myStop/GTFS-Realtime.ashx?Type=TripUpdate",
        "realtime_alerts": "https://foothilltransit.rideralerts.com/myStop/GTFS-Realtime.ashx?Type=Alert"
      },
      "license": {
        "url": "http://foothilltransit.org/about/developer-resources/developer-license-agreement/"
      },
      "authorization": {
        "type": "ip_address",
        "info_url": "http://foothilltransit.org/about/developer-resources/"
      }
    }