## 现有协议 

GET api/category

returns
```json
{
  "status": 200,
  "msg": "ok",
  "data": [
    {
      "id": 10,
      "pid": 0,
      "cate_name": "活动",
      "pic": "http://kaifa.crmeb.net/uploads/attach/2020/03/20200318/2c9fd486092555d91efff5c6e5e383d6.jpg",
      "children": [
        {
          "id": 1,
          "cate_name": "天天免单",
          "pic": "http://kaifa.crmeb.net/uploads/attach/2020/03/20200318/f1c66db0b9bb23d7b36013d794492d67.jpg"
        },
        {
          "id": 2,
          "cate_name": "活动2",
          "pic": "http://kaifa.crmeb.net/uploads/attach/2020/03/20200318/2ab5ea85f26c5bcdf2559136c7a3b22d.jpg"
        },
        {
          "id": 3,
          "cate_name": "活动N",
          "pic": "http://kaifa.crmeb.net/uploads/attach/2020/03/20200318/2c9fd486092555d91efff5c6e5e383d6.jpg"
        },
        {
          "id": 199,
          "cate_name": "黑洞",
          "pic": "http://kaifa.crmeb.net/uploads/attach/2020/03/20200318/2c9fd486092555d91efff5c6e5e383d6.jpg"
        }
      ]
    }
  ]
}
// 说明
- 协议格式不变
- 商品类活动都在"活动"分类下, 其 id 固定为 10
- 子分类中, id 从 1 往后排
- 挖矿活动 id 固定为 199
```