Annotation and module

[Rémi Forax]

The current spec disallows to put annotations on a module,
while I understand why nodody want to have an artifact descriptor 
defined using
annotations, I think this is too restrictive.

Eclipse, by example, has an annotation named @NonNullByDefault that
you can put on a package to improve the null-analysis.
I think this kind of annotations should be allowed on a module.

Perhaps, only annotations visible at runtime should be disallowed.

cheers,
Rémi