remove $Id markers

git-svn-id: http://caml.inria.fr/svn/ocaml/trunk@14620 f963ae5c-01c2-4b8c-9fe0-0dff7051ff02
merge COMPFLAGS and OPTCOMPFLAGS

git-svn-id: http://caml.inria.fr/svn/ocaml/trunk@14621 f963ae5c-01c2-4b8c-9fe0-0dff7051ff02