Fixed bug with ssl error handling.

        try:

            buf = self._sock.recv(RpcConnection.RECV_BUF_SIZE)

        except socket.error as err:

            if err.errno == 11:

                # Errno 11 -> retry again

                logging.debug('Non critical error while reading a socket:'

                                ' %r', err)

            if isinstance(err, socket.error) and err.errno == 11:

                return

            elif isinstance(err, ssl.SSLError) and err.errno == 2:

                return

            else:

                raise err

        if not buf:

            # Empty buffer = closed socket.