* Copyedit the page
A few minor updates were made.
* Update conjuction
Three options. The first (original) was OK, the second (change in this PR) was ambiguous, the third is a bit clearer.
* 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.