Gappa does not need this cleaning, but the human who reads generated files does.

export Why3's extended hash tables as Stdlib.XHashtbl
in order to keep OCaml's Hashtbl accessible. Unlike Stdlib.Map
which fully covers the OCaml's interface, Stdlib.XHashtbl does
not provide polymorphic hash tables.

Util now is a small module containing misc functions.

+ fix a bug in "compare"

+ rename Debug.Opt to Debug.Args to avoid conflicts

+ add an explanation comment in src/util/stdlib.ml*

+ create AUTHORS file
+ fix the linking exception in LICENSE
+ update the "About" in IDE
+ remove the trailing whitespace
+ inflate my scores at Ohloh