asciidoctor: add page (#6455)

pages/common/asciidoctor.md

@@ -0,0 +1,20 @@
+# asciidoctor
+
+> A processor that converts AsciiDoc files to a publishable format.
+> More information: <https://docs.asciidoctor.org>.
+
+- Convert a specific `.adoc` file to HTML (the default output format):
+
+`asciidoctor {{path/to/file.adoc}}`
+
+- Convert a specific `.adoc` file to HTML and link a CSS stylesheet:
+
+`asciidoctor -a stylesheet={{path/to/stylesheet.css}} {{path/to/file.adoc}}`
+
+- Convert a specific `.adoc` file to embeddable HTML, removing everything except the body:
+
+`asciidoctor --embedded {{path/to/file.adoc}}`
+
+- Convert a specific `.adoc` file to a PDF using the `asciidoctor-pdf` library:
+
+`asciidoctor --backend={{pdf}} --require={{asciidoctor-pdf}} {{path/to/file.adoc}}`