net/ipaddr: New port: Command-line IP address manipulation tool

ipaddr is a command-line tool for manipulating and querying IP addresses
and networks. It provides functionality similar to Python's ipaddress module
but as a standalone CLI utility.

Features include:
- IPv4 and IPv6 address normalization
- CIDR and netmask prefix notation support
- Network calculations (network, broadcast, host addressing)
- Address classification (private, loopback, multicast, etc.)
- Subnet and supernet operations
- Command chaining for complex operations
- IPv6-specific features (6to4, Teredo, zone-id)

WWW: https://github.com/astralblue/ipaddr

PR:		292621
Reported by:	Eugene M. Kim <ab@astral.blue> (new maintainer)