7.6: added new oper notice flags:
        server_connect, an autoconnect or CONNECT command was started;
        user_killed, any user was killed;
        user_nick_change, any user changed his nick;
        user_join, any user joined a channel;
        account_register, an account was registered;
        account_login, a user authenticated to an account;
        account_logout, a user logged out from an account.