How to use the gulp-concat-util.footer function in gulp-concat-util

options.paths.sources + 'tools/css.class.js',
        options.paths.sources + 'tools/detector.class.js',
        options.paths.sources + 'tools/ga_tags.class.js',
        options.paths.sources + 'tools/keyboard.class.js',
        options.paths.sources + 'tools/konami_code.class.js',
        options.paths.sources + 'tools/mouse.class.js',
        options.paths.sources + 'tools/offline.class.js',
        options.paths.sources + 'tools/registry.class.js',
        options.paths.sources + 'tools/resizer.class.js',
        options.paths.sources + 'tools/strings.class.js',
        options.paths.sources + 'tools/ticker.class.js',
        options.paths.sources + 'tools/viewport.class.js',
    ] )
    .pipe( concat( 'burno-' + options.version + '.js' ) )
    .pipe( concat.header( before ) )
    .pipe( concat.footer( after ) )
    .pipe( concat.header( signature ) )
    .pipe( gulp.dest( options.paths.destination ) )
    .pipe( uglify() )
    .pipe( concat.header( signature ) )
    .pipe( rename( { extname : '.min.js' } ) )
    .pipe( gulp.dest( options.paths.destination ) );

    // Without polyfill
    gulp.src( [
        options.paths.sources + 'core/b.class.js',
        options.paths.sources + 'core/abstract.class.js',
        options.paths.sources + 'core/event_emitter.class.js',

        options.paths.sources + 'tools/browser.class.js',
        options.paths.sources + 'tools/colors.class.js',
        options.paths.sources + 'tools/css.class.js',

gulp.task('sass:critical', function() {
  return gulp.src('css/main.css')
    // wrap with style tags
    .pipe(concat.header('<style>'))
    .pipe(concat.footer('</style>'))
    // convert it to an include file
    .pipe(rename({
        basename: 'criticalCSS',
        extname: '.html'
      }))
    // insert file in the includes folder
    .pipe(gulp.dest('_includes/'));
    });

gulp.task("default", () => {
  return gulp
    .src("../../templates/libraries/**/package.json")
    .pipe(
      concat(".wcflibcache.json", {
        process: function(src, filePath) {
          return src + ",";
        }
      })
    )
    .pipe(concat.header("["))
    .pipe(concat.footer("{}]"))
    .pipe(gulp.dest("./"));
});

gulp.task('scripts', function() {
    return gulp.src([
      options.tmp + '**/*.js'
    ])
    .pipe(ngAnnotate())
    .pipe(angularFilesort())
    .pipe(concat('xosHpc.js'))
    .pipe(concat.header('//Autogenerated, do not edit!!!\n'))
    .pipe(concat.footer(TEMPLATE_FOOTER))
    .pipe(uglify())
    .pipe(gulp.dest(options.static + 'js/'));
  });

gulp.task('scripts', function() {
    return gulp.src([
      options.tmp + '**/*.js'
    ])
    .pipe(ngAnnotate())
    .pipe(angularFilesort())
    .pipe(concat('xosDeveloper.js'))
    .pipe(concat.header('//Autogenerated, do not edit!!!\n'))
    .pipe(concat.footer(TEMPLATE_FOOTER))
    .pipe(uglify())
    .pipe(gulp.dest(options.static + 'js/'));
  });

gulp.task('scripts', function() {
    return gulp.src([
      options.tmp + '**/*.js'
    ])
    .pipe(ngAnnotate())
    .pipe(angularFilesort())
    .pipe(concat('xosUITutorial.js'))
    .pipe(concat.header('//Autogenerated, do not edit!!!\n'))
    .pipe(concat.footer(TEMPLATE_FOOTER))
    .pipe(uglify())
    .pipe(gulp.dest(options.static + 'js/'));
  });

gulp.task('scripts', function() {
    return gulp.src([
      options.tmp + '**/*.js'
    ])
    .pipe(ngAnnotate())
    .pipe(angularFilesort())
    .pipe(concat('xosTruckroll.js'))
    .pipe(concat.header('//Autogenerated, do not edit!!!\n'))
    .pipe(concat.footer(TEMPLATE_FOOTER))
    .pipe(uglify())
    .pipe(gulp.dest(options.static + 'js/'));
  });

gulp.task('critical', function() {
  return gulp.src('public/css/critical.css')
    .pipe(concat.header('<style>'))
    .pipe(concat.footer('</style>'))
    .pipe(rename({
        basename: 'critical',
        extname: '.html'
    }))
    .pipe(gulp.dest('craft/templates/_css'));
});

gulp.task('cmd', function() {
  var stream = gulp.src('src/**/*.js')
    .pipe(concat.header('define(function(require, exports, module) {\n'))
    .pipe(concat.footer('\n});'))
    .pipe(gulp.dest("./build/cmd/"))
  return stream;

});