common-grpc: update deps & **require Node v4**
common-grpc: update deps & **require Node v4**

GoogleCloudPlatform/gcloud-node,GoogleCloudPlatform/gcloud-node,googleapis/google-cloud-node,jgeewax/gcloud-node,GoogleCloudPlatform/gcloud-node,callmehiphop/gcloud-node,callmehiphop/gcloud-node,googleapis/google-cloud-node,jgeewax/gcloud-node,googleapis/google-cloud-node,googleapis/google-cloud-node