Terms for specified facet

`facet_id`: "topics", "facility", "format", "genre", or "rights".

GET /api/0.2/facet/format/children/
HTTP 200 OK
Allow: GET, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "total": 3,
    "page_size": 25,
    "prev": null,
    "next": null,
    "hits": [],
    "aggregations": {},
    "objects": [
        {
            "id": "format-av",
            "model": "ddrfacetterm",
            "facet": "format",
            "term_id": "av",
            "links": {
                "json": "http://ddr.densho.org/api/0.2/facet/format/av/",
                "html": "http://ddr.densho.org/browse/format/av/",
                "objects": "http://ddr.densho.org/api/0.2/facet/format/av/objects/"
            },
            "title": "Audio/Visual",
            "description": "AV DESCRIPTION"
        },
        {
            "id": "format-ds",
            "model": "ddrfacetterm",
            "facet": "format",
            "term_id": "ds",
            "links": {
                "json": "http://ddr.densho.org/api/0.2/facet/format/ds/",
                "html": "http://ddr.densho.org/browse/format/ds/",
                "objects": "http://ddr.densho.org/api/0.2/facet/format/ds/objects/"
            },
            "title": "Dataset",
            "description": "DS DESCRIPTION"
        },
        {
            "id": "format-doc",
            "model": "ddrfacetterm",
            "facet": "format",
            "term_id": "doc",
            "links": {
                "json": "http://ddr.densho.org/api/0.2/facet/format/doc/",
                "html": "http://ddr.densho.org/browse/format/doc/",
                "objects": "http://ddr.densho.org/api/0.2/facet/format/doc/objects/"
            },
            "title": "Document",
            "description": "DOC DESCRIPTION"
        },
        {
            "id": "format-img",
            "model": "ddrfacetterm",
            "facet": "format",
            "term_id": "img",
            "links": {
                "json": "http://ddr.densho.org/api/0.2/facet/format/img/",
                "html": "http://ddr.densho.org/browse/format/img/",
                "objects": "http://ddr.densho.org/api/0.2/facet/format/img/objects/"
            },
            "title": "Still Image",
            "description": "IMG DESCRIPTION"
        },
        {
            "id": "format-vh",
            "model": "ddrfacetterm",
            "facet": "format",
            "term_id": "vh",
            "links": {
                "json": "http://ddr.densho.org/api/0.2/facet/format/vh/",
                "html": "http://ddr.densho.org/browse/format/vh/",
                "objects": "http://ddr.densho.org/api/0.2/facet/format/vh/objects/"
            },
            "title": "Oral History",
            "description": "VH DESCRIPTION"
        }
    ]
}