[nem-en] Debugging macros again

[vc]

> > We talk about generating fake code for macros generated AST. Maybe time
> to
> > return to this problem?
> 
> I implemented this some time ago? Is it not usable?

I don't try it. But it solution work only for added top level code (not for
expression macros).

PS

BTW, in debugger exists many small problems like this:
http://nemerle.org/bugs/view.php?id=821
http://nemerle.org/bugs/view.php?id=819