Add Watch Bookmarks support

[wojtek-t]

Enhancement Description

• One-line enhancement description (can be used as a release note): Add support for watch bookmarks to reduce load on kube-apiserver
• Kubernetes Enhancement Proposal: KEP: watch bookmarks
• Primary contact (assignee): wojtek-t
• Responsible SIGs: sig-apimachinery, sig-scalability
• Enhancement target (which target equals to which milestone):
  • Alpha release target (1.15)
  • Beta release target (1.16)
  • Stable release target (1.17)

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

[k8s-ci-robot]

@wojtek-t: There are no sig labels on this issue. Please add a sig label.

A sig label can be added by either:

1. mentioning a sig: @kubernetes/sig-<group-name>-<group-suffix>
   e.g., @kubernetes/sig-contributor-experience-<group-suffix> to notify the contributor experience sig, OR

2. specifying the label manually: /sig <group-name>
   e.g., /sig scalability to apply the sig/scalability label

Note: Method 1 will trigger an email to the group. See the group list.
The <group-suffix> in method 1 has to be replaced with one of these: bugs, feature-requests, pr-reviews, test-failures, proposals

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/test-infra repository.

[kacole2]

Thanks @wojtek-t. When coding begins please drop all k/k PRs here for tracking purposes.

/stage alpha

[wojtek-t]

Ref kubernetes/kubernetes#73585

[mrbobbytables]

@wojtek-t we're doing a KEP review for enhancements to be included in the Kubernetes v1.15 milestone. After reviewing your KEP, it's currently missing a test plan which is required information per the KEP Template. Please update the KEP to include the required information before the Kubernetes 1.15 Enhancement Freeze date of 4/30/2019.