Start network with DHCP

[flaviojs]

Currently the iso does not start network connections automatically, but /etc/motd says "Ethernet and Wi-Fi connections using DHCP should work automatically".

Within the cdrom systemctl start dhcpcd systemd-networkd makes the network connections automatically go up with DHCP, so either /etc/motd needs to be updated with that information (since Installation_guide and the install procedure requires a working network) or the services need to be enabled during iso creation.

[flaviojs]

Turns out the files that enable the services were supposed to be symlinks.
Instead of that the configs had normal files that systemd was ignoring.