Classes
 ClassDescription
 CommandEvent CommandEvents are fired when single commands finish executing, finish undoing or are cancelled.
 CommandHistory Provides an interface to manage undo/redo history and fires events on the eventDispatcher when history events occur.
 HistoryEvent These events fire when operations occur on a CommandHistory object, or to control a CommandHistory object.
 UndoableCommand This command handles adding itself to the provided/injected CommandHistory.
 UndoableCommandBase