title: Bootstrap 4 tabs not wrapping
body: <p><strong>Problem happens in alpha 6 but not alpha 5</strong></p>
  
  <p>In bootstrap 3 tabs would wrap onto the next line so they could be used on smaller screen sizes.</p>
  
  <p>In Bootstrap 4 they don't wrap and poke off the side of the screen.  This is example from the Bootstrap 4 documentation.</p>
  
  <p>How do i make it wrap like in bootstrap 3?</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-css lang-css prettyprint-override"><code>#viewport
  {
    width: 200px;
    border: 1px solid #000;
  }</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-alpha.6/css/bootstrap.min.css" integrity="sha384-rwoIResjU2yc3z8GV/NPeZWAv56rSmLldC3R/AZzGRnGxQQKnKkoFVhFQhNUwEyJ" crossorigin="anonymous"&gt;
  
  &lt;script src="https://code.jquery.com/jquery-3.1.1.slim.min.js" integrity="sha384-A7FZj7v+d/sdmMqp/nOQwliLvUsJfDHW+k9Omg/a/EheAdgtzNs3hpfag6Ed950n" crossorigin="anonymous"&gt;&lt;/script&gt;
  &lt;script src="https://cdnjs.cloudflare.com/ajax/libs/tether/1.4.0/js/tether.min.js" integrity="sha384-DztdAPBWPRXSA/3eYEEUWrWCy7G5KFbe8fFjk5JAIxUYHKkDx6Qin1DkWx51bBrb" crossorigin="anonymous"&gt;&lt;/script&gt;
  &lt;script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-alpha.6/js/bootstrap.min.js" integrity="sha384-vBWWzlZJ8ea9aCX4pEW3rVHjgjt7zpkNpZk+02D9phzyeVkE+jo0ieGizqPLForn" crossorigin="anonymous"&gt;&lt;/script&gt;
  
  &lt;div id="viewport"&gt;
  &lt;!-- Nav tabs --&gt;
  &lt;ul class="nav nav-tabs" role="tablist"&gt;
    &lt;li class="nav-item"&gt;
      &lt;a class="nav-link active" data-toggle="tab" href="#home" role="tab"&gt;Home&lt;/a&gt;
    &lt;/li&gt;
    &lt;li class="nav-item"&gt;
      &lt;a class="nav-link" data-toggle="tab" href="#profile" role="tab"&gt;Profile&lt;/a&gt;
    &lt;/li&gt;
    &lt;li class="nav-item"&gt;
      &lt;a class="nav-link" data-toggle="tab" href="#messages" role="tab"&gt;Messages&lt;/a&gt;
    &lt;/li&gt;
    &lt;li class="nav-item"&gt;
      &lt;a class="nav-link" data-toggle="tab" href="#settings" role="tab"&gt;Settings&lt;/a&gt;
    &lt;/li&gt;
  &lt;/ul&gt;
  
  &lt;!-- Tab panes --&gt;
  &lt;div class="tab-content"&gt;
    &lt;div class="tab-pane active" id="home" role="tabpanel"&gt;...&lt;/div&gt;
    &lt;div class="tab-pane" id="profile" role="tabpanel"&gt;...&lt;/div&gt;
    &lt;div class="tab-pane" id="messages" role="tabpanel"&gt;...&lt;/div&gt;
    &lt;div class="tab-pane" id="settings" role="tabpanel"&gt;...&lt;/div&gt;
  &lt;/div&gt;
  
  &lt;/div&gt;</code></pre>
  </div>
  </div>
  </p>
  
  <p>(black outline shows small viewport.  On previous version the tabs would wrap to new line so all would be visible inside the black line)</p>