title: Bootstrap checkbox/radio buttons do not change <input> value
body: <p>The <a href="http://getbootstrap.com/javascript/#buttons-usage">JavaScript page for Bootstrap</a> shows some nice use of buttons to style checkboxes and radio fields. For example, for a checkbox, I might write</p>
  
  <pre><code>&lt;div class="btn-group" data-toggle="buttons"&gt;
    &lt;label class="btn btn-primary"&gt;
      &lt;input type="checkbox"&gt; Option 1
    &lt;/label&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>However, the library doesn't actually change the value of the underlying <code>&lt;input&gt;</code> field -- it just changes whether the <code>&lt;label&gt;</code> field has class <code>active</code>.  I would have expected it to change the <code>checked</code> attribute on the checkbox.  Apparently I don't just have it misconfigured -- this is the way the examples on the Bootstrap site work.</p>
  
  <p>Is this actually expected behavior? If so, it seems fairly useless, as people are going to want to use the checkbox field. If not, how do I properly configure Bootstrap checkboxes/radio buttons?</p>