code: function append(file, text, options) {
    options = _.sanitize(options, {atNewLine: false, encoding: 'utf-8'});
  
    if (!exists(file)) {
      write(file, text, {encoding: options.encoding});
    } else {
      if (options.atNewLine && !text.match(/^\n/) && exists(file)) text = `\n${text}`;
      fs.appendFileSync(file, text, {encoding: options.encoding});
    }
  }
docs: Add text to file
  @function $file~append
  @param {string} file - File to add text to
  @param {string} text - Text to add
  @param {Object} [options]
  @param {string} [options.encoding=utf-8] - Encoding used to read/write the file
  @param {boolean} [options.atNewLine=false] - Force the added text to start at a new line
  @example
  // Append new lines to 'Changelog' file
  $file.append('Changelog', 'Added new plugins');