About the init system, Trisquel uses Upstart and the /etc/init directory is
the main place where you configure startup scripts/jobs. The old System V
init scripts still exist in /etc/init.d and /etc/rc?.d directories because
they are still in the process of being moved to Upstart.
It is expected to switch from Upstart to systemd in the future, but I don't
think this will be very soon for Trisquel.
About iptables, why are you setting those rules? It seems pointless to me.
It doesn't give you any security. A connection on a given port can't happen,
if there aren't any programs listening there. Maybe I'm reading the rules
wrong since I rarely use iptables.
For HTTP servers, you can also give nginx a try. It's light, flexible,
fairly easy to start with and more widely used than lighttpd.
