Graceful node shutdown

# Enhancement Description
- One-line enhancement description (can be used as a release note): Kubelet can detect and gracefully terminate pods during a node shutdown. Ref: https://github.com/kubernetes/kubernetes/issues/91472
- Kubernetes Enhancement Proposal: https://github.com/kubernetes/enhancements/tree/master/keps/sig-node/2000-graceful-node-shutdown
- Discussion Link:
- Primary contact (assignee): @bobbypage
- Responsible SIGs: sig/node
- Enhancement target (which target equals to which milestone):
- Alpha release target (1.20)
- Beta release target (1.21)
- Stable release target (TBD)
* [x] Alpha (related PRs, can be assigned to a specific track later)
* [x] KEP (`k/enhancements`) update PR(s):
* [x] https://github.com/kubernetes/enhancements/pull/2001
* [x] https://github.com/kubernetes/enhancements/pull/2063
* [x] https://github.com/kubernetes/enhancements/pull/2295
* [x] Issues and Code (`k/k`) update PR(s): https://github.com/kubernetes/kubernetes/pull/96129
* [x] Docs (`k/website`) update(s): https://github.com/kubernetes/website/pull/24918
* [x] Beta (related PRs, can be assigned to a specific track later)
* [x] KEP (`k/enhancements`) update PR(s):
* [x] https://github.com/kubernetes/enhancements/pull/2472
* https://github.com/kubernetes/enhancements/pull/3131
* [x] Issues and Code (`k/k`) update PR(s):
* [x] https://github.com/kubernetes/kubernetes/pull/98658
* [x] https://github.com/kubernetes/kubernetes/pull/99735
* [x] Docs (`k/website`) update(s): https://github.com/kubernetes/website/pull/27335
- GA
* [ ] KEP (`k/enhancements`) update PR(s):
* [x] https://github.com/kubernetes/enhancements/pull/4640
* [ ] Issues and Code (`k/k`) update PR(s): some test and bugfix after beta
* [x] 1.22 https://github.com/kubernetes/kubernetes/pull/102840
* [x] https://github.com/kubernetes/kubernetes/pull/103566
* [x] 1.32 https://github.com/kubernetes/kubernetes/pull/125070
* Blockers/GA criteria
- [ ] https://github.com/kubernetes/kubernetes/issues/122912
- [x] https://github.com/kubernetes/kubernetes/issues/122122
- [ ] https://github.com/kubernetes/kubernetes/issues/105780
- [ ] https://github.com/kubernetes/kubernetes/issues/116965
- [ ] https://github.com/kubernetes/kubernetes/issues/112443
* [ ] Docs (`k/website`) update(s):

_Please keep this description up to date. This will help the Enhancement Team to track the evolution of the enhancement efficiently._

Start with the linked Kubernetes Enhancement Proposal and the checked-off alpha, beta, and GA pull requests to understand the completed work. The remaining unchecked GA blockers and documentation updates define what is still outstanding; verify their status before attempting any change.

Written by the indexing model from the issue text.