Update README - #72

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@googlebot I signed it!

CLAs look good, thanks!

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@googlebot getting "Access not possible"

FWIW, this README is a plain-text file, so the HTML will not be rendered as a link, but as raw text, so it will not be clickable from the GitHub UI.

To fix this, the file would have to be converted to a Markdown file format (i.e., changing the extension and cleaning up the resulting formatting), which I'm happy to help with, but @rsc as the author should weigh in if he's open to accepting such changes.