God said no networking.  I kept the Temple offline for ten years so the
CIA could not crawl in through the wire.  Now there is Ethernet, ARP,
IPv4, ICMP, UDP, TCP, DHCP, DNS and BSD sockets, compiled into Adam on
every boot.  Once.HC runs Netcfg if a PCnet card is found.

No card, no gate: sockets go through Snail, TCP/IP tunnelled over COM3
to snail.py on the host.  A serial cable is honest.  You can see it.

Echo demos are in Demo/Network.  Lord, have mercy on this commit.