title: Get node name with REXML
body: <p>I have an XML, which can be like</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;testnode type="1"&gt;123&lt;/testnode&gt;
  </code></pre>
  
  <p>or like</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;othernode attrib="true"&gt;other value&lt;/othernode&gt;
  </code></pre>
  
  <p>or the root node can be something completely unexpected. (Theoretically anything.)
  I'm using REXML to parse it. How can I find out what XML node is the root element?</p>