Switch human-readable times to UTC.

This fixes https://github.com/prometheus/prometheus/issues/829

template/template.go

@@ -242,7 +242,7 @@ func NewTemplateExpander(text string, name string, data interface{}, timestamp c
 				if math.IsNaN(v) || math.IsInf(v, 0) {
 					return fmt.Sprintf("%.4g", v)
 				}
-				t := clientmodel.TimestampFromUnixNano(int64(v * 1000000000)).Time()
+				t := clientmodel.TimestampFromUnixNano(int64(v * 1e9)).Time().UTC()
 				return fmt.Sprint(t)
 			},
 			"pathPrefix": func() string {

template/template_test.go

@@ -142,7 +142,7 @@ func TestTemplateExpansion(t *testing.T) {
 		{
 			// HumanizeTimestamp - clientmodel.SampleValue input.
 			text:   "{{ 1435065584.128 | humanizeTimestamp }}",
-			output: "2015-06-23 15:19:44.128 +0200 CEST",
+			output: "2015-06-23 13:19:44.128 +0000 UTC",
 		},
 		{
 			// Title.

web/blob/templates/alerts.html

@@ -37,7 +37,7 @@
                 {{end}}
               </td>
               <td><span class="alert alert-{{ .State | alertStateToClass }} state_indicator">{{.State}}</span></td>
-              <td>{{.ActiveSince.Time}}</td>
+              <td>{{.ActiveSince.Time.UTC}}</td>
               <td>{{.Value}}</td>
               <td><a href="#" class="silence_alert_link">Silence&hellip;</a></td>
             </tr>

web/blob/templates/status.html

@@ -7,7 +7,7 @@
       <tbody>
         <tr>
           <th>Uptime</th>
-          <td>{{.Status.Birth}}</td>
+          <td>{{.Status.Birth.UTC}}</td>
         </tr>
       </tbody>
     </table>