# Functions
GetIPZeroAddress returns INADDR_ANY or INADDR6_ANY (according sysctl disable_ipv6).
IsLoopbackAddress checks if the address is IPv4 / IPv6 loopback address.
NormalizeIPAddress returns normalized IP, adding square brackets for IPv6 if needed, Already Normalized IPv6 addresses, or invalid IPv6 addresses will stay unchanged.
# Variables
GetLoopbackAddress returns IPv4 / IPv6 loopback address (according sysctl disable_ipv6).