Updated tests for both IPv4 and IPv6 testing.

Your hosts file may list localhost only as "127.0.0.1", but "::1" as
"ip6-localhost". This settings differs between many distributions/OSs;
Debian is set up correctly, for example.

Shed is only tested using IPv4, warp is tested using both protocols.

This problem may be solved by modifying the parser in a way that it also accepts
addresses like "[::1]".