• Prepare for Socket::getaddrinfo() in core; prefer it to
  Socket::GetAddrInfo::getaddrinfo()
  
• Implement Family constructor arg
  
• Optional registration with IO::Socket
  
• Documentation rewordings
  
• Bugfix to local socket connect tests - test using blocking rather
  than nonblocking sockets to guarantee synchronous packet delivery
  
• Bugfix to t/04, t/05 - skip if unable to bind ::1