title: Download XML file from RSS feed
body: <p>as the title states, I'm trying to download the XML file from the RSS feed, however, I'm not sure how it is done in Objective-C, I've tried to use <code>stringWithContentsOfURL</code> for an <code>NSString</code>, however, that didn't work and I'm not quite sure why.</p>
  
  <p>If anyone has any advice about how to achieve the download and why <code>stringWithContentsOfURL</code> didn't work please help</p>