[MERGE][bug 276868] Blacklist pyrex 0.9.4.1

[Mark Hammond]

> > I think in general we're a bit too tolerant of people running without
> > compiled extensions and therefore seeing bad performance, and we
> > should do something about that.  Maybe setup.py should fail unless
> you
> > specify --without-compiled-extensions or something.  But that's
> beyond
> > the scope of this patch.
> >
> 
> Actually, I was thinking about something along those lines. Only more
> specifically so that PQM would fail if it could not build the
> extensions.

If the name was chosen appropriately, we could also apply it to the binary build process on Windows, so it too would fail if it was trying to build an "official" or "preferred" or whatever configuration and certain modules couldn't be located (either due to a build failure, or failure to install the package, or any other reason.)  I like the idea of less scope for human error in these important processes...

Mark