title: bootstrap 4 img-fluid does not change image height
body: <p>Responsive Images in Bootstrap 4, with class .img-fluid are resized disproportionally. They keep it's height even width is shrinking down correctly. That is deforming whole image. Is there any way how to make it as smooth as it was in Bootstrap 3 with class .img-responsive? Thanks</p>
  
  <pre><code>&lt;div class="col-sm-6"&gt;
      &lt;img class="img-fluid" src="/assets/blogs/14853991244821.jpg" alt=""&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>By the way it is same in Bootstrap 4 documentation (<a href="https://v4-alpha.getbootstrap.com/content/images/" rel="noreferrer">https://v4-alpha.getbootstrap.com/content/images/</a>) where sample svg image keeps height 250 pixels regardless of it's width.</p>