How to use the jake.mkdirP function in jake

separator: '\n'
  });
  console.log('Created ' + JSONEDITOR_CSS);

  // minify the css file
  write(JSONEDITOR_CSS_MIN, new CleanCSS().minify(String(read(JSONEDITOR_CSS))));

  // create a folder img and copy the icons
  jake.mkdirP('./img');
  jake.cpR(jsoneditorSrc + 'css/img/jsoneditor-icons.png', './img/');
  console.log('Copied jsoneditor-icons.png to ./img/');

  // copy assets
  // concatenate and copy ace files
  var aceSrc = './node_modules/ace/build/src-min/';
  jake.mkdirP(BUILD_ACE);
  concat({
    src: [
          aceSrc + 'ace.js',
          aceSrc + 'ext-searchbox.js',
          aceSrc + 'mode-json.js',
          aceSrc + 'theme-textmate.js',
          jsoneditorSrc + 'js/ace/theme-jsoneditor.js'
    ],
    dest: BUILD_ACE + 'ace.js',
    separator: '\n'
  });
  jake.cpR(aceSrc + 'worker-json.js', BUILD_ACE);

  // copy and minify json lint file
  jake.mkdirP(BUILD_JSONLINT);
  minify({

src: [
      jsoneditorSrc + 'css/jsoneditor.css',
      jsoneditorSrc + 'css/contextmenu.css',
      jsoneditorSrc + 'css/menu.css',
      jsoneditorSrc + 'css/searchbox.css'
    ],
    dest: JSONEDITOR_CSS,
    separator: '\n'
  });
  console.log('Created ' + JSONEDITOR_CSS);

  // minify the css file
  write(JSONEDITOR_CSS_MIN, new CleanCSS().minify(String(read(JSONEDITOR_CSS))));

  // create a folder img and copy the icons
  jake.mkdirP('./img');
  jake.cpR(jsoneditorSrc + 'css/img/jsoneditor-icons.png', './img/');
  console.log('Copied jsoneditor-icons.png to ./img/');

  // copy assets
  // concatenate and copy ace files
  var aceSrc = './node_modules/ace/build/src-min/';
  jake.mkdirP(BUILD_ACE);
  concat({
    src: [
          aceSrc + 'ace.js',
          aceSrc + 'ext-searchbox.js',
          aceSrc + 'mode-json.js',
          aceSrc + 'theme-textmate.js',
          jsoneditorSrc + 'js/ace/theme-jsoneditor.js'
    ],
    dest: BUILD_ACE + 'ace.js',

task('build', {async: true}, function () {
  jake.mkdirP(DIST);
  jake.mkdirP(DIST + '/img');

  // concatenate and stringify the css files
  concat({
    src: [
      './src/timeline/component/css/timeline.css',
      './src/timeline/component/css/panel.css',
      './src/timeline/component/css/labelset.css',
      './src/timeline/component/css/itemset.css',
      './src/timeline/component/css/item.css',
      './src/timeline/component/css/timeaxis.css',
      './src/timeline/component/css/currenttime.css',
      './src/timeline/component/css/customtime.css',

      './src/timeline/component/css/dataaxis.css',
      './src/timeline/component/css/pathStyles.css',

task('build', {async: true}, function () {
  jake.mkdirP(DIST);
  jake.mkdirP(DIST + '/img');

  // concatenate and stringify the css files
  concat({
    src: [
      './src/timeline/component/css/timeline.css',
      './src/timeline/component/css/panel.css',
      './src/timeline/component/css/labelset.css',
      './src/timeline/component/css/itemset.css',
      './src/timeline/component/css/item.css',
      './src/timeline/component/css/timeaxis.css',
      './src/timeline/component/css/currenttime.css',
      './src/timeline/component/css/customtime.css',

      './src/timeline/component/css/dataaxis.css',
      './src/timeline/component/css/pathStyles.css',

jake.mkdirP(BUILD_ACE);
  concat({
    src: [
          aceSrc + 'ace.js',
          aceSrc + 'ext-searchbox.js',
          aceSrc + 'mode-json.js',
          aceSrc + 'theme-textmate.js',
          jsoneditorSrc + 'js/ace/theme-jsoneditor.js'
    ],
    dest: BUILD_ACE + 'ace.js',
    separator: '\n'
  });
  jake.cpR(aceSrc + 'worker-json.js', BUILD_ACE);

  // copy and minify json lint file
  jake.mkdirP(BUILD_JSONLINT);
  minify({
    src: './node_modules/jsonlint/lib/jsonlint.js',
    dest: BUILD_JSONLINT + 'jsonlint.js'
  });
});

task('bundle', {async: true}, function () {
  var b = browserify();

  // make directory dist
  jake.mkdirP(DIST);

  b.add(INDEX);
  b.bundle({
    standalone: 'mathjs'
  }, function (err, code) {
    if(err) {
      throw err;
    }

    // add header and shim to code
    var lib = util.read(HEADER) + code;

    // write bundled file
    util.write(MATHJS, lib);

    // update version number and stuff in the javascript files

task('zip', ['build', 'minify'], {async: true}, function () {
  var pkg = 'jsoneditor-' + version();
  var zipfile = BUILD + pkg + '.zip';
  jake.mkdirP(BUILD);

  var output = fs.createWriteStream(zipfile);
  var archive = archiver('zip');

  archive.on('error', function(err) {
    throw err;
  });

  archive.pipe(output);

  var filelist = new jake.FileList();
  filelist.include([
    'README.md',
    'NOTICE',
    'LICENSE',
    'HISTORY.md',