title: Convert an arbitrary string to xml in ruby
body: <p>If I have a string which may contain any characters (including '/', '&amp;',etc...) how do convert it safely into XML that can be stored like this:</p>
  
  <pre><code>&lt;myelement&gt;mystring&lt;/myelement&gt;
  </code></pre>
  
  <p>Does it need to be CDATA, or can I easily convert it using a ruby function?</p>