* The main page's title appears in search results, so use "The Racket
Language" instead of "Racket". Additional minor tweaks to a few more
titles to make them presentable as search results.
* Add a `#:description' keyword to make it easy to add it to pages. Add
such texts to the main page, downloads, community, learning, people,
and mailing list pages.
* Add a <meta name="robots" content="NOODP" /> to the front page, to
avoid getting the ODP (dmoz) blurb, hopefully the new and improved
description(s) will be used instead. (If not, this should be
reverted.)
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