configs/releng/airootfs/etc/systemd/network/20-{ethernet,wirless}.network:
Making sure that systemd-networkd enables DHCP capabilities also for
IPv6 ('DHCP=yes' and unsetting IPv6AcceptRA - see `man 5
systemd.network` for further information).
Closes#23
Adding a numerical prefix ('20-') to the ethernet.network and
wireless.network configuration files for systemd-networkd.
This way overriding them can become more predictable e.g. by providing
files with a '30-' prefix.
Closes#13