fix seccomp for the new event loop add/remove syscalls from the BPF filter and move sandbox() after libevent initialisation

improve logs management

added prefork option

add the ``entrypoint'' option

added ``block return'' and ``strip'' options

missing argument for LOGI

avoid race-condition what if we receive a SIGHUP right after unblock_signal (or during the whole block_signals...unblock_signals) but *before* the wait_sighup? Yeah.

reload configuration on SIGHUP

drop unnecessary check around close

refactor executor_main now it's symmetrical to listener_main().

refactoring startup logic

drop privileges after the fork

configless: fixing the case of the implicit "." I got bitten by the scope visibility rules. After the end of the block, the path variable is no longer valid, and in fact later load_vhosts fails to open that (because the buffer gets invalidated)

ensure absolute paths in config-less mode

set cloexec status on the socketpair fds the executor forks to spawn the cgi scripts, and they inherit the socket for communication with the listener process. Make that impossible.