Integrate build and documentation of Ltac2

Since Ltac2 cannot be put under the stdlib logical root (some file names
would clash), we move it to the `user-contrib` directory, to avoid adding
another hardcoded path in `coqinit.ml`, following a suggestion by @ejgallego.

Thanks to @Zimmi48 for the thorough documentation review and the
numerous suggestions.

1 files changed, 5 insertions, 0 deletions

diff --git a/tools/coqdep.ml b/tools/coqdep.ml
index 7114965a11..8823206252 100644
--- a/tools/coqdep.ml
+++ b/tools/coqdep.ml
@@ -529,6 +529,11 @@ let coqdep () =
     add_rec_dir_import add_known "plugins" ["Coq"];
     add_rec_dir_import (fun _ -> add_caml_known) "theories" ["Coq"];
     add_rec_dir_import (fun _ -> add_caml_known) "plugins" ["Coq"];
+    let user = "user-contrib" in
+    if Sys.file_exists user then begin
+      add_rec_dir_no_import add_known user [];
+      add_rec_dir_no_import (fun _ -> add_caml_known) user [];
+    end;
   end else begin
     (* option_boot is actually always false in this branch *)
     Envars.set_coqlib ~fail:(fun msg -> raise (CoqlibError msg));