Return the list of public data files.

GET /api/public-data/?created_end=2%2F14%2F2016&created_start=2%2F14%2F2016&format=api&source=direct-sharing-139
HTTP 200 OK
Allow: GET, HEAD, OPTIONS
Cache-Control: max-age=0, no-cache, no-store, must-revalidate
Content-Type: application/json
Expires: Wed, 24 Apr 2024 22:19:29 GMT
Vary: Accept

{
    "count": 0,
    "next": null,
    "previous": null,
    "results": []
}