The Markdown package converts CommonMark markup to TeX commands. The
functionality is provided both as a Lua module and as plain TeX, LaTeX, and
ConTeXt macro packages that can be used to directly typeset TeX documents
containing markdown markup. Unlike other converters, the Markdown package
does not require any external programs, and makes it easy to redefine how
each and every markdown element is rendered.  Creative abuse of the markdown
syntax is encouraged.
