update contrib: building reference docs

[kbhawkey]

This is a Bug Report

Problem
The contrib pages for generating the reference docs are outdated. The required
golang version, the build dependencies, the generated directory structure, and the update-imported-docs script has changed.

Proposed Solution:
Rewrite the contribute pages outlining the changes.

Page to Update:
https://kubernetes.io/docs/contribute/generate-ref-docs/

• Add a new page which outlines a streamlined approach to building all of the reference doc components.
• Create another page which details the common setup instructions for generating the
  reference docs without the script (manually setting up the required repositories).
  The supporting reference doc instructions will link to the setup instructions.

[kbhawkey]

/assign

[fejta-bot]

Issues go stale after 90d of inactivity.
Mark the issue as fresh with /remove-lifecycle stale.
Stale issues rot after an additional 30d of inactivity and eventually close.

If this issue is safe to close now please do so with /close.

Send feedback to sig-testing, kubernetes/test-infra and/or fejta.
/lifecycle stale

[kbhawkey]

/close

[k8s-ci-robot]

@kbhawkey: Closing this issue.

In response to this:

/close

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.