Improve handling of externally set initial population in PSO - minor change.

src/eva2/server/go/enums/PSOTopologyEnum.java

@@ -44,7 +44,8 @@ public enum PSOTopologyEnum {
 		case 4: return tree;
 		case 5: return hpso;
 		case 6: return random;
+		default:	System.err.println("Error: invalid old topology ID in PSOTopologyEnum translateOldID! Returning grid.");
+			return grid; 
 		}
-	   return random;
 	}
 }