Reloading of users is not logged

If users are reloaded and the contents change, there is no trace of this in the log. This can cause hard to track problems when the source or the contents of the database users changes due to some external reason e.g. restoring a database.

Simply logging whenever users are reloaded would be too verbose. To prevent flooding the logs with irrelevant information, the message should only be logged when the contents change.