[Umbrella] Refactor the Release Engineering Handbooks

[xmudrii]

This issue is an umbrella issue to track the progress of refactoring the release engineering handbooks.

• Split the Branch Management handbook into multiple handbooks
  • Release Management handbook
    • Improve the handbook formatting and wording
    • Document how alpha.1 releases should be handled (alpha.1 documentation #1229)
    • Consider adding a diagram describing the release process (Add basic release engineering description #1088)
  • Branch Management handbook
    • Ensure the handbook is up to date
    • Improve the handbook formatting and wording
• Merge the Patch Release Team handbook with the other handbooks
• Consider moving the role-handbooks in the filesystem tree above other documents
• Document the needed IAM privileges for running tasks mentioned in the handbooks

/kind documentation
/area release-eng
/priority important-soon
/milestone v1.20
/assign

[xmudrii]

cc: @kubernetes/release-engineering
If you have any feedback regarding our handbooks, please feel free to leave it here.

[saschagrunert]

I like that proposal 👍

Do we still have an onboarding document after those changes? Generally spoken, those two sections:

• https://github.com/kubernetes/sig-release/blob/667bf705e2fe9350fb12f3ba09bb5380f6b01a63/release-engineering/role-handbooks/branch-manager.md#overview
• https://github.com/kubernetes/sig-release/blob/667bf705e2fe9350fb12f3ba09bb5380f6b01a63/release-engineering/role-handbooks/branch-manager.md#prerequisites

[xmudrii]

@saschagrunert I propose that we have some general/onboarding handbook that would be common for all other handbooks. It would include most of the things from those two links, and eventually some other useful references as well.

[lasomethingsomething]

@pmmalinov01 interested in helping with this--what are some break-out tasks he could get started with?