Use Host header to select Hyves

Although `NAME.hyves.nl` isn't always resolvable, using that as the Host header value and retrieving hyves.nl seems to do fine.

Unfortunately, the links in the page themselves still point to the unresolvable domain, which means that we won't get much out of this:

1. `--recursive` with `--level inf` could mean that we'll grab _everything_ under hyves.nl.
2. The links won't be followable.

The WARCs might be a bit odd, too.

That said, I'm putting this up for review if anyone wants to take a hack at making it better.