We have a new feature for BurgeCMF, 2d logging system, which allows different modules to have their specific logging system without implementing it. For example a module may require to log events about customers, another one to log events about product prices. Now, it is possible to call two functions from Log_manager_model: log_2d(), get_logs_2d(). The first one writes the log, and the second one retreives them, and there is no need to implement new logging system. It's also needed for these modules to map event_types (strings) to event_types_indexes (integers). The 2d-logging system just knows event_type_index.