ChannelObserver interface and implementations

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	Interface	Description
	ChannelObserver	Interface to be implemented by classes that wish to observe one or more channels.

	Class	Description
	ChannelActivityEvent	Event that fires when a group of observed channels switches its state from inactive to active or vice versa.
	ChannelActivityObserver	ChannelObserver implementation that observes the level of activity for one or more channels.
	SessionTimeoutEvent	Event fired by SessionTimeoutObservers.
	SessionTimeoutObserver	ChannelObserver implementation that observes the idle time of one or more channels to fire events if the server-side session is about to expire.