CONTRIBUTING.md: add author identity info

[emaste]

Summary

We do not want @users.noreply.github.com addresses.

[imp]

So I like this wording for non-trivial changes. I fear it will cause too much friction for the typo report or wording tweak.

CONTRIBUTING.md

123

Yea. To get author we need this.

But for trivial changes, I'd be good with some variation of submitted by, noticed by or whatever. In that case you have just a name, or gtt66 on irc or github user HangChad2000.

[emaste]

CONTRIBUTING.md

123

Fair enough - I was thinking of this specifically for pull requests. I could move it up to the pull request section and make it ### Author Name and Email perhaps

[emaste]

Move Author Name and Email section to a subsection of pull requests