title: How to add a breakline inside a cell with Excel4node module in NodeJs
body: <p>I need to insert a multiline cell with module <a href="https://www.npmjs.com/package/excel4node" rel="nofollow noreferrer">excel4node</a>, in documentation I didn't found anything about this.
  I tried to insert the escape sequence <code>"\n"</code> but it didn't work. This is my code:</p>
  
  <pre><code>var xl = require('excel4node');
  var wb = new xl.Workbook();
  var ws = wb.addWorksheet('Sheet 1');
  
  ws.cell(1, 1).string('first line \n second line');
  </code></pre>
  
  <p>And this is the result inside the cell:</p>
  
  <pre><code>first line \n second line
  </code></pre>
  
  <p>Somebody knows how it's possible to insert a multiline cell? Which char must I use?</p>