Use GCD to serialize access to open-sockets dictionary.
Added support for expected read-count. Though that's probably not useful :-)
Note that fcntl() isn't available either.
Manually bridge fcntl() and ioctl() (both varargs). ioctl(FIONREAD) still doesn't seem to work.
Added fcntl support, specifically the NIO flag.
Add some chaining ( sock.onRead {} .onClose {}).
Merge branch 'release/0.0.9'