The examples make up the majority of the front page, and it turns out
that google used some of these links in "sitelinks" in search result.
These links should be the main entry points, and we ended up having such
gems as "Printf" be there. They provide a way to "demote" URLS so they
won't show there, but doing that for one link means that another will
pop in (and there's a limit of a 100 such demotions). So add this in an
attempt to make it not consider them as things that can be used in the
sitelinks. This might be reverted if it doesn't help.
(Note that this is discouraged as a way to "sculpt pagerank", but the
purpose here is not to affect how they crawl the web pages and make page
reputation flow, but only to cover up for a missing feature that ends up
with horrible sitelinks. The pages are scanned anyway from the doc
pages.)
necessary modules are now "all.rkt"s; "shard.rkt"s turn to
"resources.rkt".
Also, "navbar.rkt" changes to "all.rkt", since it was doing the same
thing (in addition to setting the navbar).
Ie, the difference between using it as a language and as a module is now
the same in both. Also, improve `scribble/html' (and
`scribble/html/htmllang') by reproviding most of the corresponding text
modules.
Change `meta/web' accordingly, and improve code by making a new langugae
(`#lang meta/web'). This language is similar to `scribble/html' except
that it uses the plain scribble reader (not the `-inside' one), it
doesn't use the customized module-begin feature (that uses
`output-xml'), and it adds all the relevant bits of `meta/web/common'.
(Also, "meta/web/common.rkt" is gone, since it's used only as a language
now.)
This commit has lots of details and binding games, so it's tricky, and
potentially caused some problems. (Took me a while to track many
breakages, so I won't be surprised if there are more.)
