controller: various fixes for the deployment controller

Changes:
* moved waiting for synced caches before starting any work
* refactored worker() to really quit on quit
* changed queue to a ratelimiting queue and added retries on errors
* deep-copy deployments before mutating - we still need to deep-copy
replica sets and pods

pkg/controller/deployment/util/deployment_util.go

@@ -753,3 +753,15 @@ func ResolveFenceposts(maxSurge, maxUnavailable *intstrutil.IntOrString, desired
 
 	return int32(surge), int32(unavailable), nil
 }
+
+func DeploymentDeepCopy(deployment *extensions.Deployment) (*extensions.Deployment, error) {
+	objCopy, err := api.Scheme.DeepCopy(deployment)
+	if err != nil {
+		return nil, err
+	}
+	copied, ok := objCopy.(*extensions.Deployment)
+	if !ok {
+		return nil, fmt.Errorf("expected Deployment, got %#v", objCopy)
+	}
+	return copied, nil
+}