Improve workflow UI to retrieve a list of operation lists from Event Broker

In the development of the Event Broker Changes UI component, an attempt was made to retrieve a list of operation lists from the Event Broker service, to avoid the need to insert the operation list identifier into the interface (Guid). However, the FIM portal seemed to struggle with the service contract reference in the UI, for no clear reason. Debugging UI components in the portal proved to be quite difficult, with trace logs not even revealing the source of error. In the interest of progress, further research into this was cut, but may be revisited at a later stage.