响应处理

Alamofire.request(.GET, "https://httpbin.org/get", parameters: ["foo": "bar"])
     .responseJSON { response in
         print(response.request)  // original URL request
         print(response.response) // URL response
         print(response.data)     // server data
         print(response.result)   // result of response serialization

         if let JSON = response.result.value {
             print("JSON: \(JSON)")
         }
     }