Update EFGen Interface Health Tags To Allow For Better Status Monitoring

The current EFGen interface "Status" health tag displays a value of "Good" if it is connected to the data source but does not factor in if it is writing Event Frame data to PI. There is not currently a straightforward way to drive a PI Notification to alert that there may be an interface issue in the scenario that the interface is connected to the data source but can not write event frames. Either the criteria for what results in a status of "Good" needs to be revisited to include both connectivity to the source data as well as actively writing Event Frames, or a new parameter should exist to allow end users to see when the last successful Event Frame was written. That would allow users to send notifications if new event frames have not been written for a certain number of hours or days, so that a PI Administrator may inspect the interface to ensure it is operating as expected.