ENH REQ: Add 'nf_nat_ipv6.ko' to kernel.

[Paul Kronenwetter]

If there’s room, please enable ‘CONFIG_IP6_NF_NAT=m’ in the kernel build and provide ‘ng_nat_ipv6.ko’ in the build.

This may enable manual (scripted) configuration of IPv6’s Unique Local Address support. My ISP changes my IPv6 prefix when the router reboots.