IPv6 support

[JanC]

Hi, does this actually work on IPv6? I see that you use a sockaddr_in instead of sockaddr_in6 in GCNetworkReachabilitySetSocketAddress

The IPv4 structs should not be used based on what Apple said in WWDC (session "Your App and Next Generation Networks")

[Coeur]

You are right, there is a bug here if trying to monitor an ipv6 address, as inet_pton() requires allocating more space in that case.

But as GCNetworkReachability is a dead project...