Since the client can be hidden from the server via multiple layers, be
they load balancers, proxies or iptable rules, it is simpler to not have
the server aware of those layers and have to inform the client of them,
instead use information the client already has.
Still missing:
remove host/port, let client use same as url it was served on.
remove other flags no longer relevant.
better mapping of server config to avoid double work?
