NamedPipe conformance tests

[Dan Kegel]

A couple questions:

1. Is anyone working on NamedPipe conformance tests?
If not, I'd be happy to try.  (Might be a challenge
to scare up a Server version of Windows, so initially
I'd just write the tests on Wine, and make sure they
compiled with winelib and with vc++.)

2. Since CreateNamedPipe is only available on Server
versions of Windows, we need a way to avoid running the
test on non-server versions.   Er, I suppose checking for
the presence of CreateNamedPipe would be the way to go :-)
I at first tried detecting the Windows version, but that's far too hairy.
- Dan