Kubelet should have a max think time before auto resync

The sync frequency should be part of the syncLoop and resync no
less often than every X seconds.  The current implementation runs
even if a config update was delivered less than X seconds ago.

cmd/kubelet/kubelet.go

@@ -148,16 +148,12 @@ func main() {
 		dockerClient,
 		cadvisorClient,
 		etcdClient,
-		*rootDirectory)
+		*rootDirectory,
+		*syncFrequency)
 
 	// start the kubelet
 	go util.Forever(func() { k.Run(cfg.Updates()) }, 0)
 
-	// resynchronize periodically
-	// TODO: make this part of PodConfig so that it is only delivered after syncFrequency has elapsed without
-	// an update
-	go util.Forever(cfg.Sync, *syncFrequency)
-
 	// start the kubelet server
 	if *enableServer {
 		go util.Forever(func() {