title: ion-buttons start and end syntax makes no sense
body: <p>I have two problems with <strong><code>ion-buttons</code></strong>. </p>
  
  <ol>
  <li><p>The ionic documentation only shows usage of the <strong><code>ion-buttons</code></strong> element with no real explanation beyond what you can infer from the example. </p></li>
  <li><p>What throws me off about this is the close tags appear to me to be in the wrong place. </p></li>
  </ol>
  
  <p>When I saw this on the docs I wondered if it was a mistake, but I've also seen this in a code example here on stack. Like this one:  </p>
  
  <pre><code>&lt;ion-header&gt;
    &lt;ion-navbar primary&gt;
      &lt;ion-buttons start&gt;       **// here it starts.**
        &lt;button menuToggle&gt;
          &lt;ion-icon name="menu"&gt;&lt;/ion-icon&gt;
        &lt;/button&gt;
      &lt;/ion-buttons&gt;  **//Why does ion-buttons close here?** 
  
      &lt;ion-title&gt;
        My Page
      &lt;/ion-title&gt;
  
      &lt;ion-buttons end&gt; **// END here?** 
        &lt;button  ion-button icon-only&gt;
          &lt;ion-icon name="search"&gt;&lt;/ion-icon&gt;
        &lt;/button&gt;
      &lt;/ion-buttons&gt; **// then close AGAIN here when there is no companion open tag?**
    &lt;/ion-navbar&gt;
  &lt;/ion-header&gt;
  </code></pre>