Automatic merge from submit-queue

Ubuntu: Enable ssh compression when downloading binaries during cluster creation

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resolves #20971 by using the options provided by ssh. 

Native ssh compression has existed for years, and the server is free to disregard the setting, so this should be safe.

With things like the kube binaries I see about a 2x speed increase. 

```
λ time scp kubes-bin.tar   9.30.182.251:/mnt/build/kubin
kubes-bin.tar                                                                                                            100%  344MB  10.7MB/s   00:32

real	0m32.284s
user	0m1.679s
sys	0m1.263s

λ time scp -C kubes-bin.tar   9.30.182.251:/mnt/build/kubin
kubes-bin.tar                                                                                                            100%  344MB  22.9MB/s   00:15

real	0m14.810s
user	0m12.858s
sys	0m0.994s

λ ls -lah kubes-bin.tar
-rw-r--r--  1 mhb  staff   344M Jun  2 15:29 kubes-bin.tar

λ tar -tf kubes-bin.tar
kubectl
master/
master/etcd
master/etcdctl
master/flanneld
master/kube-apiserver
master/kube-controller-manager
master/kube-scheduler
node/
node/flanneld
node/kube-proxy
node/kubelet
```