Specification Group Index Endpoint

This endpoint is only available if 
aerocargo/specifications is installed.
Structure
See View Specification Group for the structure of the specification group payloads inside the 
data array.
Example Request
GET /api/specification-groups?per_page=2
Example Response
{
    "current_page": 1,
    "data": [
        //...
    ],
    "first_page_url": "http://aero.test/api/specification-groups?page=1",
    "from": 1,
    "last_page": 3,
    "last_page_url": "http://aero.test/api/specification-groups?page=3",
    "next_page_url": "http://aero.test/api/specification-groups?page=2",
    "path": "http://aero.test/api/specification-groups",
    "per_page": 2,
    "prev_page_url": null,
    "to": 2,
    "total": 5
}
See View Specification Group for the structure of the specification group payloads inside the 
data array.