Saves the current object to the database. Determines, whether the current object has to be inserted or updated to the database.

In case of an update, the objects' updateStateToDb() method is being called (as required by \Kajona\System\System\Model). In the case of a new object, a blank record is being created. Therefore, all tables returned by class' doc comment will be filled with a new record (using the same new systemid as the primary key). The newly created systemid is being set as the current objects' one and can be used in the afterwards called updateStateToDb() method to reference the correct rows.