Drop extern (C++)

[dsimcha]

== Quote from Don (nospam at nospam.com)'s article
> BLS wrote:
> > Hi,
> > I think nearly nobody is using extern (C++) 'cause of it's limits. So
> > why not drop it ? IMHO this feature is not a " D2 sales argument",
> > instead it's vs. productive.
> > What do you think ?
> > Bjoern
> >
> There's a much more fundamental problem with it: C++ doesn't support it!
> You can't compile a file with MSVC and link it to something compiled
> with g++.
> Look up my CodeProject article on member function pointers -- every
> vendor has their own API, and virtually none of them are documented.
> On Windows, extern(C++) means extern(DMC++), but for me, the only thing
> I'd want to link to is MSVC. Much more useful would be, as Brad says, to
> provide a way of specifying the name mangling. If we could do that, we'd
> be more compatible with C++ than C++ is to itself.

This brings up another important point:  If any implementation of extern(C++) is
tied to a specific C++ compiler anyhow (probably the one made by the same people
that made the D compiler) then why the heck is it so limited?  The rationale for
it being so limited was that doing it better would practically require
implementing a C++ compiler.