namespaces "kube-system" already exists

Had to comment creation of the namespace

```
# create the kube-system
# kubectl create -f "${KUBE_ROOT}/cluster/mesos/docker/kube-system-ns.yaml"
```

may be add something like this:

kubectl get ns kube-system  /dev/null

```
if [ $? != 0; then
   # create the kube-system
   kubectl create -f "${KUBE_ROOT}/cluster/mesos/docker/kube-system-ns.yaml"
else
   echo namespace kube-system exists
fi
```
