Initial sync in the delta-MMR (syncprov + accesslog) mode may lose some entries

[erthink]

This problem became visible during fixing the #120.

Briefly:

• check fo initial state was be added by ea7e270.
• then became seen that some (seems a first and near) entries had not been replicated from the master server to the (at least one) consumer.

[erthink]

The rare conditions are needed repoduce this bug, so change priority to 'minor'.

In other words:

• we could make a release;
• code is even better than before.

[erthink]

В сущности это проявление проблемы, ранее уже замеченной и описанной в #102

Её устранение требует серьёзной доработки. Возможно что разумным выходом будет отключение/удаление некоторых возможностей или изменение протокола (потеря совместимости с OpenLDAP).