(* given an uri u it returns the list of tokens of the base uri of u *)
(* e.g.: token_of_uri "cic:/a/b/c/d.xml" returns ["a" ; "b" ; "c"] *)
(* given an uri u it returns the list of tokens of the base uri of u *)
(* e.g.: token_of_uri "cic:/a/b/c/d.xml" returns ["a" ; "b" ; "c"] *)