2.1.2: keyserver route failure

[Robert J. Hansen]

> I'm not convinced that it's gnupg's job to compensate for 
> unreasonably-configured IPv6 stacks that think they have a route but 
> actually don't.

Nor am I, but the world has never much cared whether something was my
job: it concerns itself more with ensuring there are consequences for
the job going undone.

At the very least, if we're not going to address the problem we should
(a) reach out to Apple about the problem and (b) document for OS X users
that GnuPG's keyserver functionality may be broken on that platform.