Automatic merge from submit-queue
Remove kubectl namespace command
**What this PR does / why we need it**:
It removes deprecated `kubectl namespace` command, which `has been superseded by the context.namespace field of .kubeconfig files. See 'kubectl config set-context --help' for more details`. It was done nearly two years ago, so like `// TODO remove once people have been given enough time to notice` comment says it may be a good time to get rid of it.
**Special notes for your reviewer**:
None ATM.
**Release note**:
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```release-note
Remove kubectl namespace command
```
Automatic merge from submit-queue
Add get/delete cluster, delete context to kubectl config
Fixes#29794 by adding `get-clusters`, `delete-cluster` and `delete-context` actions to `kubectl config`.
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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It cordons (marks unschedulable) the given node, and then deletes every
pod on it, optionally using a grace period. It will not delete pods
managed by neither a ReplicationController nor a DaemonSet without the
use of --force.
Also add cordon/uncordon, which just toggle node schedulability.
Just do all doc generation in the hack::util::gen-docs instead of spread
around. We also only track the generated docs in a single file for the
whole tree.
