title: Maxlength property of input field is not respected
body: <p>I have the following React method which should create an input field with a maximum length:</p>
  
  <pre><code>displayInputField: function(name, placeholder, updateMethod, maxLength) {
          return (
              &lt;div className="form-group form-inline"&gt;
                  &lt;label&gt;{name}&lt;/label&gt;
                  &lt;input onChange={updateMethod} type="text" className="form-control"
                       maxlength={maxLength} placeholder={placeholder}/&gt;
  
              &lt;/div&gt;
          );
      },
  </code></pre>
  
  <p>However, the input field generated does not stop me from inputting more characters.
  Its source is this:</p>
  
  <pre><code>&lt;input type="text" class="form-control" placeholder="&lt;15 characters" data-reactid=".0.1.2.0.0.1.2.1.0.1"&gt;
  </code></pre>
  
  <p>Why is the maxlength attribute not respected?</p>