change randomNeighbors such that it works both with gephi and without

src/main/java/fucoin/wallet/AbstractWallet.java

@@ -182,15 +182,19 @@ public abstract class AbstractWallet extends AbstractNode implements Serializabl
         overlayNeighbours.add(wallet);
     }
 
-    //TODO: ????!???
-	/*@Override
+	@Override
 	public ActorRef getRandomNeighbor() {
-		List<ActorRef> neighbors = new ArrayList<>(overlayNeighbours);
+		List<ActorRef> neighbors;
+		if (overlayNeighbours != null && !overlayNeighbours.isEmpty()) {
+			neighbors = new ArrayList<>(overlayNeighbours);
+		} else {
+			neighbors = new ArrayList<>(getKnownNeighbors().values());
+		}
 		if (getExcludedNeighbors().size() < neighbors.size()) {
 			neighbors.removeAll(getExcludedNeighbors());
 		}
 		Random rand = new Random();
 		int index = rand.nextInt(neighbors.size());
 		return neighbors.get(index);
-	}*/
+	}
 }