title: using v-model on <select> makes first option not appear in select
body: <p>My HTML:</p>
  
  <pre><code>&lt;select id='select-id' v-model='position'&gt;
      &lt;option&gt;Opt 1&lt;/option&gt;
      &lt;option&gt;Opt 1&lt;/option&gt;
  &lt;/select&gt;
  </code></pre>
  
  <p>The Vue component:</p>
  
  <pre><code>var app = new Vue({
      el: '#elementid',
      data: {
          name: '',
          position: 'Select Option',
      },
  });
  </code></pre>
  
  <p>When they select an option, I'm using v-model to send that value to the data variable 'name' (will be using this for other things).</p>
  
  <p>However, visually, the select box is blank until I open it and select an option. If I remove the v-model it works as usual with Option 1 being visiable as the preselected option. I've even tried presetting the 'name' to 'Select Option'. I've tried using the html5 'selected disabled' attributes.</p>