Change the type of socket-buffer to fast-io:output-buffer.
Call close-socket when exiting an event-loop.
Optimize a little bit.
Replace iolib/syscalls by woo.ev.syscall.

Since iolib/sockets depends on iolib/syscalls, it is needed anyway,
however woo.ev.syscall is closer to metal and a little bit faster.
Timeout (15 min) for idle sockets.
Make flush-buffer safety.
vom logger functions allows only string as its first argument.
Fix in case the body is null or pathname.
Check if the socket is still open in flush-buffer because it may be closed in write-cb.