Setups the DB, creates admin and public roles if they don't exist.

def create_db(self):
        """
            Setups the DB, creates admin and public roles if they don't exist.
        """
        self.add_role(self.auth_role_admin)
        self.add_role(self.auth_role_public)
        if self.count_users() == 0:
            log.warning(LOGMSG_WAR_SEC_NO_USER)