Base objects for plugin creation and communication

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	Interface	Description
	Plugin	The Plugin interface defines rules for IoC plugin implementation.
	PluginListener	The PluginListener interface defines rules for objects which want to listen all of plugin events.

	Class	Description
	AbstractPlugin	Abstract implementation of Plugin.
	ChannelExpert	The ChannelExpert class is a repository for EventChannel object.
	NullPlugin	The NullPlugin class defines a default plugin to use if none is defined current application.
	PluginBroadcaster	The PluginBroadcaster class extends EventBroadcaster to add dedicated Plugin features.
	PluginChannel	The PluginChannel class defines event channel for a target plugin.
	PluginDebug	The PluginDebug class defines "logging tunnel" for plugin logging feature.
	PluginEvent	The PluginEvent class represents the event object passed to the event listener for Plugin events.