Unsubscribe an event handler(s) from an event. If a specific handler is specified for an event, only that handler will be unsubscribed. Otherwise all handlers will be unsubscribed for that event.
The name of the event to unsubscribe
Optionally the specific handler to unsubscribe
Subscribe an event handler to a particular event name, multiple handlers per event name are allowed.
The name of the event to subscribe to
The handler callback to fire on this event
Once listens to an event once then auto unsubscribes from that event
The name of the event to subscribe to once
The handler of the event that will be auto unsubscribed