feat(cmd/curl): include timings in JSON output

The PerfOps API returns timings in curl responses, that this command
line tool was ignoring. This CL adds this field to the internal
structs, so that it will be marshalled for output.

Bug: #35

Author: terinjokes

perfops/run.go

@@ -56,6 +56,7 @@ type (
 		Output   interface{} `json:"output,omitempty"`
 		Message  string      `json:"message,omitempty"`
 		Finished interface{} `json:"finished"`
+		Timing   *RunTiming  `json:"timing,omitempty"`
 	}
 
 	// RunItem represents an item of an MTR or ping output.
@@ -72,6 +73,14 @@ type (
 		Items     []*RunItem `json:"items,omitempty"`
 	}
 
+	// RunTiming represents the test timings.
+	RunTiming struct {
+		Total   float64 `json:"total,omitempty,string"`
+		DNS     float64 `json:"dns,omitempty,string"`
+		Connect float64 `json:"connect,omitempty,string"`
+		TTFB    float64 `json:"ttfb,omityempty,string"`
+	}
+
 	// DNSPerfRequest represents the parameters for a DNS perf request.
 	DNSPerfRequest struct {
 		Target    string  `json:"target,omitempty"`