code: function getAllFolders(dir, folderlist) {
      const files = fs.readdirSync(dir);
      folderlist = folderlist || [];
      files.forEach((file) => {
          if (fs.statSync(path.join(dir, file)).isDirectory()) {
              folderlist = getAllFolders(path.join(dir, file), folderlist);
              folderlist.push(path.join(dir, file));
          }
      });
      return folderlist;
  }
docs: List all folders in a directory
  
  @param {dir} dir - Current folder.
  @param {object} folderlist - List of folders already found.
  @returns {object} - List of all folders in dir