migrate documentation for the AsciiDoc language

docs/asciidoc/antora.yml

docs/asciidoc/modules/ROOT/nav-compare.adoc

docs/asciidoc/modules/ROOT/nav.adoc

docs/asciidoc/modules/ROOT/pages/asciidoc-vs-markdown.adoc

docs/asciidoc/modules/ROOT/pages/comment.adoc

docs/asciidoc/modules/ROOT/pages/doctypes.adoc

docs/asciidoc/modules/ROOT/pages/elements.adoc

docs/asciidoc/modules/ROOT/pages/index.adoc

docs/asciidoc/modules/ROOT/partials/glossary.adoc

docs/asciidoc/modules/ROOT/partials/to-latest-syntax.adoc

docs/asciidoc/modules/attributes/examples/counter.adoc

docs/asciidoc/modules/attributes/examples/id.adoc

docs/asciidoc/modules/attributes/nav-ref.adoc

docs/asciidoc/modules/attributes/nav.adoc

...iidoc/modules/attributes/pages/assignment-precedence.adoc

.../asciidoc/modules/attributes/pages/attribute-entries.adoc

...dules/attributes/pages/attribute-entry-substitutions.adoc

...asciidoc/modules/attributes/pages/boolean-attributes.adoc

...sciidoc/modules/attributes/pages/built-in-attributes.adoc

docs/asciidoc/modules/attributes/pages/counter.adoc