Small correction in method to write stats computation for average

src/main/java/be/cylab/java/wowa/training/Utils.java

@@ -540,9 +540,6 @@ final class Utils {
                 new FileOutputStream(filename, true),
                 StandardCharsets.UTF_8)) {
 
-            writer.write("___________________________________________\n");
-            writer.write("|TRIGGER VALUE       :" + trigger_value + "\n");
-            writer.write("|_________________________________________|\n");
             writer.write("AVERAGE\n\n");
             writer.write("Average true positive : "
                     + average_true_positive_counter + "\n");