Issue
In EventUtils, module and system group IDs are declared as modules/ and systems/ respectively, yet in implementation, only the system group ID is used properly while the ModuleRegistry uses its own group ID declared as urn:osh:modules.
Group ID for module events is urn:osh:modules
Topic IDs for module events are the module's ID.
Importance
This makes it harder to subscribe to a specific module's events or the module group if this is not known to a developer.
Solution
ModuleRegistry should use the group ID and topic IDs that EventUtils provides. This requires a change in ModuleRegistry and AdminUI.