[Work in progress] Updating the contribution guidelines

[zacharysarah]

🛑 DO NOT MERGE 🛑

This PR's goal is to improve the Kubernetes contribution guidelines.

This megabranch consolidates multiple related PRs into a single topic branch.

PR	Filename	Description	Contributing	⚡ Done
TBD	README.md	Clarify the contribution process, consider sharing content with main Contributing page. Provide a clear entry point for new contributors by linking to repo issues labeled P3 and Actionable.
TBD	create-pull-request.md	Creating a Documentation Pull Request: Change title to Create a Pull Request Change headings to: Before you begin Fork the Kubernetes documentation repository Make your changes Submit a pull request Work with reviewers Forking: make local changes in a topic branch on their fork, not master Consolidate branch comparison sections

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This change is 

[steveperry-53]

@zacharysarah, Don't move editdocs.md until you discussed it with the team. I seem to remember there's a reason that it is in its current location.

[chenopis]

@zacharysarah @steveperry-53 So can we close this PR then?

[zacharysarah]

@chenopis Yes, let's close it. We may come back to this, but it'll be a ways down the road if we do.