feat(master): check the registry now from the service page (#35)

internal/master/web/views.go

@@ -281,6 +281,15 @@ func versionRows(versions []model.ImageVersion, actualDigest string) []versionRo
 	return rows
 }
 
+// pollBlocked returns why the registry cannot be checked for svc, or "" when
+// it can.
+func pollBlocked(svc model.Service) string {
+	if svc.RemovedAt != nil {
+		return model.ReasonRemoved
+	}
+	return poller.SkipReason(svc)
+}
+
 // pollingStatus is the text of the "Polling" row on the service page and
 // whether it is a registry error.
 func pollingStatus(svc model.Service, interval time.Duration) (text string, failed bool) {