A Markdown frontend in pure OCaml.

This Markdown library is implemented using only pure OCaml (including
I/O operations provided by the standard OCaml compiler distribution).
OMD is meant to be as faithful as possible to the original Markdown.
Additionally, OMD implements a few Github markdown features, an
extension mechanism, and some other features. Note that the opam
package installs both the OMD library and the command line tool `omd`.
