title: How to put plain text into navbar in bootstrap4
body: <p>In <code>bootstrap3</code>, there is this <code>.navbar-text</code> to use, so I can put some plain text into navbar. Something like "Signed in as xxx". </p>
  
  <p>But in <code>bootstrap4</code>, I can't find the class to put plain text into <code>.navbar</code>. There is only <code>.navlink</code>.</p>
  
  <p>This <a href="http://v4-alpha.getbootstrap.com/components/navbar/" rel="nofollow">document</a> seems not revearling enough information. </p>