update Automaton

include/automaton.hpp

@@ -27,6 +27,7 @@ public:
     virtual ~Automaton();
 
     void setAlphabet(const Alphabet&);
+    const Alphabet& getAlphabet() const {return alphabet;}
     void setNeighborhoodRule(NeighborhoodRule*);
     NeighborhoodRule* getNeighborhoodRule() const;
     void setTransitionRule(TransitionRule*);