Process queries for HexGrid objects.
:param request: HTTP GET request
:return: JSON format of HexGrid (only pk and count) or GeoJSON of the geom of HexGrid.

GET /api/occurrence/grid/?taxon=9544
HTTP 200 OK
Allow: OPTIONS, GET
Content-Type: application/json
Vary: Accept

{
    "features": [
        {
            "properties": {
                "pk": "442801"
            },
            "type": "Feature",
            "geometry": {
                "coordinates": [
                    [
                        [
                            [
                                2250004.77906584,
                                -866025.807569065
                            ],
                            [
                                2333338.15125337,
                                -721688.17297422
                            ],
                            [
                                2500004.89562843,
                                -721688.17297422
                            ],
                            [
                                2583338.26781595,
                                -866025.807569065
                            ],
                            [
                                2500004.89562843,
                                -1010363.44216391
                            ],
                            [
                                2333338.15125337,
                                -1010363.44216391
                            ],
                            [
                                2250004.77906584,
                                -866025.807569065
                            ]
                        ]
                    ]
                ],
                "type": "MultiPolygon"
            }
        }
    ],
    "crs": {
        "type": "name",
        "properties": {
            "name": "EPSG:3031"
        }
    },
    "type": "FeatureCollection"
}