simulator: correctly implement TMLCommand

TMLNotifiedCommand, unlike many other child classes, does not implement
the virtual functions getNbOfChannels() and getChannel() of its parent
class TMLCommand. Implement them by exposing its sole channel.

simulators/c++2/src_simulator/app/TMLNotifiedCommand.h

@@ -63,6 +63,8 @@ public:
 	virtual ~TMLNotifiedCommand(){}
 	void execute();
 	inline TMLChannel* getChannel() const {return dynamic_cast<TMLChannel*>(_channel);}
+	inline unsigned int getNbOfChannels() const {return 1;}
+  inline TMLChannel* getChannel(unsigned int iIndex) const {return getChannel();}
 	std::string toString() const;
 	std::string toString(TMLLength aLength, TMLLength aProgress) const;
 	std::string toShortString() const;