Introduce cherry-pick tools

[RainbowMango]

What would you like to be added:

• : cherry-pick tooks, like Kubernetes hack/cherry_pick_pull.sh
• : cherry-pick document at docs/contributors/devel/cherry-picks.md, like this one

Why is this needed:

[jameszhangyukun]

/assign I want to try two tasks

[carlory]

@jameszhangyukun

Sorry, I did not notice this issue, I have already submitted a related PR #1216

/assign

[RainbowMango]

@jameszhangyukun Have you started this task?

[jameszhangyukun]

@jameszhangyukun Have you started this task?

I just read https://github.com/kubernetes/kubernetes/blob/master/hack/cherry_pick_pull.sh do not begin this task

[RainbowMango]

So, how do you want to move this issue forward? You can help review #1216 or submit a new PR, it's up to you.

@carlory Thanks for your contribution, but since this issue has been claimed by @jameszhangyukun , I need confirmation before moving your PR. Hope you can understand.

[jameszhangyukun]

So, how do you want to move this issue forward? You can help review #1216 or submit a new PR, it's up to you.

@carlory Thanks for your contribution, but since this issue has been claimed by @jameszhangyukun , I need confirmation before moving your PR. Hope you can understand.

If he finish this issue.I think you can receive his PR. This is ok

[carlory]

@RainbowMango @jameszhangyukun

sorry, it's my mistake. I will be more careful next time.

[jameszhangyukun]

@RainbowMango @jameszhangyukun

sorry, it's my mistake. I will be more careful next time.

It doesn't matter.Don't blame yourself.

[RainbowMango]

@carlory Don't get me wrong, It's not your fault.

We are following the first-come-first-serve rule, all contributor's efforts are fully respected.

[RainbowMango]

Thanks @jameszhangyukun for your cooperation.