This commit reorganizes the asciidoctor attributes for the reference
documentation. Instead of being contributed partially by the build and
individual documents, attributes are now shared in common files that are
included in top sections.
This commit creates a new "framework-docs" module, which is dedicated to
documentation generation (reference and API docs).
This commit refactors the build configuration and moves the asciidoc
files to a separate location, but does not change the name nor the
nature of published artifacts.
Closes gh-29417
Brian Clozel
Sam Brannen
Sébastien Deleuze
rstoyanchev