Derive conversion functions between OCaml types and YAML
Description
This ppx is based on ppx_yojson [1] and ppx_deriving_yojson [2] because
of the many similarities between JSON and yaml. In particular many of
the ways OCaml values are encoded to yaml types are the same as those
implemented by the Yojson ppx.
References:
[1] https://github.com/NathanReb/ppx_yojson
[2] https://github.com/ocaml-ppx/ppx_deriving_yojson
