add output flag for kubectl top pod

[qyecst]

What type of PR is this?

/kind feature

What this PR does / why we need it:

add output flag -o, --output for kubectl top pod.

use -o wide or --output wide to display NODE info like:

NAME                   NODE     CPU(cores)   MEMORY(bytes)   
db-5977df8496-p8s2f    node1    1m           57Mi
one-d48cbd8b8-znqcx    node2    2m           1Mi
two-55445bbdb9-bt72c   node3    5m           2Mi

Convenient to view the pod status of the specified node: kubectl top pod -o wide | grep node-name.
Convenient to check the load and node distribution of pods: kubectl top pod -o wide -l app=label.
When sudden surge in node load, convenient to check the status of the corresponding pods.

Which issue(s) this PR fixes:

Fixes kubernetes/kubectl#1706

Special notes for your reviewer:

Does this PR introduce a user-facing change?

Add output flag [(-o|--output=)wide] for kubectl top pod command.
Can be used to output more detailed information.

Additional documentation e.g., KEPs (Kubernetes Enhancement Proposals), usage docs, etc.:

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: qyecst
Once this PR has been reviewed and has the lgtm label, please assign brianpursley for approval. For more information see the Code Review Process.

The full list of commands accepted by this bot can be found here.

Needs approval from an approver in each of these files:

• staging/src/k8s.io/kubectl/OWNERS

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[k8s-ci-robot]

This issue is currently awaiting triage.

If a SIG or subproject determines this is a relevant issue, they will accept it by applying the triage/accepted label and provide further guidance.

The triage/accepted label can be added by org members by writing /triage accepted in a comment.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository.

[k8s-ci-robot]

Welcome @qyecst!

It looks like this is your first PR to kubernetes/kubernetes 🎉. Please refer to our pull request process documentation to help your PR have a smooth ride to approval.

You will be prompted by a bot to use commands during the review process. Do not be afraid to follow the prompts! It is okay to experiment. Here is the bot commands documentation.

You can also check if kubernetes/kubernetes has its own contribution guidelines.

You may want to refer to our testing guide if you run into trouble with your tests not passing.

If you are having difficulty getting your pull request seen, please follow the recommended escalation practices. Also, for tips and tricks in the contribution process you may want to read the Kubernetes contributor cheat sheet. We want to make sure your contribution gets all the attention it needs!

Thank you, and welcome to Kubernetes. 😃

[k8s-ci-robot]

Hi @qyecst. Thanks for your PR.

I'm waiting for a kubernetes member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

I understand the commands that are listed here.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository.

[googs1025]

/ok-to-test

[k8s-ci-robot]

@qyecst: The following test failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
pull-kubernetes-linter-hints	d9fc10d	link	false	/test pull-kubernetes-linter-hints

Full PR test history. Your PR dashboard. Please help us cut down on flakes by linking to an open issue when you hit one in your PR.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository. I understand the commands that are listed here.

[googs1025]

/test pull-kubernetes-unit