Currently, --spin uses Network.BSD to look up IPv4 addresses of hostnames.
Not Ipv6.

This doesn't prevent using propellor with IPv6 only hosts. But it prevents
using short names for such hosts with --spin. And, propellor only looks at
configured ipv4 properties of a host when deciding if the DNS hostname is
out of date, and falling back to contacting the host by IPv6 address.

> [[fixed|done]] --[[Joey]]
