Operation and Operation List Comments

A new attribute to be added to the schema of both Operation and Operation List object classes, and a corresponding free text field placed in the UI, in order to allow Event Broker configurations to be documented. This attribute is to be optional and not to have any bearing whatsoever on the operation of the service or console - purely to serve as "self documentation". Server export/import functionality will need to be extended to include this new attribute for both classes.

This will also provide a means of diarising any post-deployment changes to a configuration in any given environment, as well as the initial deployed configuration by the original implementor.