Custom syntax for floating attributes: [@@@id].

git-svn-id: http://caml.inria.fr/svn/ocaml/trunk@14588 f963ae5c-01c2-4b8c-9fe0-0dff7051ff02
Fix syntax for floating attributes.

git-svn-id: http://caml.inria.fr/svn/ocaml/trunk@14589 f963ae5c-01c2-4b8c-9fe0-0dff7051ff02
Fix syntax for floating attributes (disable until next bootstrap).

git-svn-id: http://caml.inria.fr/svn/ocaml/trunk@14590 f963ae5c-01c2-4b8c-9fe0-0dff7051ff02