Add odoc rules

[leostera]

ocaml_module(
  name = "module_srcs",
  srcs = glob(["*.ml", "*.mli"]),
)

odoc_unit(
  name = "docs.odoc",
  srcs = [ ":module_srcs" ],
)

odoc_html(
  name = "docs.html",
  srcs = [ ":docs.odoc"]
)

Alternatively

ocaml_module(
  name = "module_srcs",
  srcs = glob(["*.ml", "*.mli"]),
)

odoc(
 name = "docs",
 srcs = [ ":module_srcs" ],
)