Expand description
Implementations of crate::OCamlDesc for types
that have natural equivalents in OCaml.
The OCaml description should be the corresponding data types in OCaml
This should correspond to the mapping defined in the ocaml-rs book:
<https://github.com/zshipko/ocaml-rs/blob/v1.0.0-beta.4/doc/src/02_type_conversion.md>
FIXME:
Unsigned types like uint16, uint32 and uint64 are not implemented as OCaml
does not provide types in the Stdlib for it. A custom block should be used.
Using Stdint could be a solution.