split into two processes: listener and executor this way, we can sandbox the listener with seccomp (todo) or capsicum (already done) and still have CGI scripts. When we want to exec, we tell the executor what to do, the executor executes the scripts and send the fd backt to the listener.

set SERVER_NAME to the vhost when executing CGI scripts

drop inet_ntop leftovers we switched to getnameinfo some time ago, but that call to inet_ntop remained. Fortunately, it doesn't harm, since what i wrote is overwritten by getnameinfo and the provided buffer should be large enough.

move cgi stuff to its own file