* Add info about requesting access
This includes how to get a sponsor, how to be a sponsor,
how to become a reviewer, approver, and website admin.
* Address feedback
* Reorganize docs contrib guide
* Address first round of feedback from Brad, Jared
* Standardize on 'SIG Docs'
* Address more feedback
* Rewrites to participating.md
* Tweak navigation titles
* Document PR Wrangler
* Document SIG Docs chairperson
* Fix codeblock that shows how to use <codenew>
It was being interpreted as a Hugo shortcode.
Misty Linville