Init the connection to the Riemann server.

def init(self):
        """Init the connection to the Riemann server."""
        if not self.export_enable:
            return None
        try:
            client = bernhard.Client(host=self.host, port=self.port)
            return client
        except Exception as e:
            logger.critical("Connection to Riemann failed : %s " % e)
            return None