use subclass of SocketUtil::TcpHandler that does not flush buffer at packet end
use subclass of SocketUtil::TcpHandler that does not flush buffer at packet end

Signed-off-by: Stephen Gran <e847df4a1043ee59626fa7d2628adff5eb244acd@piksel.com>

sgran/fluent-plugin-carbon,pikselpalette/fluent-plugin-carbon