Description of problem:

Users can not control events frequency or mask/acknowledge events in the system. 

For instance: with the BZ 987299 introduced, each time a physical interface is going up/down there will be a log notification. In case there is a flapping link,
the event log can easily get flooded. Sometimes this is a good thing as it shows the real-time status, but I know some customers that may want to control the frequency of some events hence this request to allow general timing configuration for all events in the system.