Add a severity to the variant

            Args:
                name (str): The name of the severity
                value : The value of the severity

def add_severity(self, name, value):
        """Add a severity to the variant

            Args:
                name (str): The name of the severity
                value : The value of the severity
        """
        logger.debug("Adding severity {0} with value {1} to variant {2}".format(
            name, value, self['variant_id']))
        self['severities'].append({name: value})