remove debug output in SM, make backlink non-optional in SM

statemachine/src/main/jastadd/mapping/SMtoDG.jrag

 aspect SMtoDG {
   syn DependencyGraph StateMachine.dependencyGraph() {
     DependencyGraph dg = new DependencyGraph();
-
     dg.setStateMachine(this);
 
     Map<State,Component> componentMap = new HashMap<>();
@@ -15,13 +14,8 @@ aspect SMtoDG {
     for (Transition t: transitions()) {
       Component to = componentMap.get(t.getTo());
       Component from = componentMap.get(t.getFrom());
-
-      //if (!from.getToList().contains(to)) {
-        logger.info("adding {} -> {}", from, to);
-
       from.addTo(to);
 
-      //}
     }
     return dg;
   }

statemachine/src/main/jastadd/mapping/SMtoDG.relast

+rel DependencyGraph.StateMachine -> StateMachine;
 rel Component.State -> State;
-rel DependencyGraph.StateMachine? -> StateMachine;