Automatic merge from submit-queue
Add a 'kubectl clusterinfo dump' option
Ref: #3500
@bgrant0607 @smarterclayton @jszczepkowski
Usage:
```
# Dump current cluster state to stdout
kubectl clusterinfo dump
# Dump current cluster state to /tmp
kubectl clusterinfo dump --output-directory=/tmp
# Dump all namespaces to stdout
kubectl clusterinfo dump --all-namespaces
# Dump a set of namespaces to /tmp
kubectl clusterinfo dump --namespaces default,kube-system --output-directory=/tmp
```
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50524c78a1
