title: Element not being disabled
body: <p>I have previously successfully implement this behaviour but for some reason it's not working. I am fairly new to Vue.js and I might be missing something.</p>
  
  <p>I have two radio buttons as such:</p>
  
  <pre><code>&lt;div class="radio"&gt;
      &lt;label&gt;
          &lt;input type="radio" name="loginRadio" id="frmLoginRadio" value="true" v-model="loginRadio" checked&gt;
          No, I am new to this site
      &lt;/label&gt;
  &lt;/div&gt;
  &lt;div class="radio"&gt;
      &lt;label&gt;
          &lt;input type="radio" name="loginRadio" id="frmRegisterRadio" value="false" v-model="loginRadio"&gt;
          Yes, my password is:
      &lt;/label&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>They both have a v-model of loginRadio which is initially set to false. When the second radio button is clicked, the disabled input button below should be enabled again. </p>
  
  <pre><code>&lt;input type="password" class="form-control" name="password" :disabled="loginRadio"&gt;
  </code></pre>
  
  <p>However, for some reason, the only thing that is happening is this (when I used Chrome Debug) </p>
  
  <pre><code>&lt;input type="password" class="form-control" name="password" disabled="false"&gt;
  </code></pre>
  
  <p>and the element stays disabled. What am I doing wrong? </p>