* build-aux/list-packages.scm (package->sxml): Add parameters previous,
description-ids and remaining, update docstring accordingly. Introduce logic
for fold-values process.
(insert-tr): Moved sxml package table-row generation to new function; remove
<a> elements and JS function calls. These are created through JS
(prep_pkg_descs). Add insert-js-call for every 15th package, and the last.
(insert-js-call): New function.
(packages->sxml): Change map to fold values; add init params.
(insert-js): show_hide: add compatibility check, introduce, use thingLink
prep: new JS function.
bulk_show_hide: new JS function.
Signed-off-by: Ludovic Courtès <ludo@gnu.org>