docs: function getAllFiles(rootFolder, dir, filelist) {
      const files = fs.readdirSync(path.join(rootFolder, dir));
      filelist = filelist || [];
      for (const file of files) {
          if (fs.statSync(path.join(rootFolder, dir, file)).isDirectory()) {
              filelist = getAllFiles(rootFolder, path.join(dir, file), filelist);
          } else {
              filelist.push(path.join(dir, file));
          }
      }
      return filelist;
  }