title: eBay API - FindItemsAdvanced call in PHP does not return any response
body: <p>Im trying to perform a simple call using ebays search API, when I make a call I get no response, and the problem is with the actual call itself.</p>
  
  <pre><code>$endpoint = 'http://open.api.ebay.com/shopping?';  
  $responseEncoding = 'XML';   
  $version = '631';   // API version number
  $appID   = 'asdf3e6e3'; 
  $itemType  = "AllItemTypes";
  $itemSort  = "EndTime";
  
  //find items advanced
  $apicalla  = "$endpoint"
      ."callname=FindItemsAdvanced"
      ."&amp;version=$version"
      ."&amp;siteid=0"
      ."&amp;appid=$appID"
      ."&amp;MaxEntries=10"
      ."&amp;ItemSort=EndTime"
      ."&amp;ItemType=AllItemTypes"
      ."&amp;IncludeSelector=SearchDetails"
      ."&amp;responseencoding=$responseEncoding";
  
      $resp = simplexml_load_file($apicalla);
  </code></pre>
  
  <p>this call is the equivalent to </p>
  
  <pre><code>http://open.api.ebay.com/shopping?callname=FindItemsAdvanced&amp;version=631&amp;siteid=0&amp;appid=asdf3e6e3&amp;MaxEntries=10&amp;ItemSort=EndTime&amp;ItemType=AllItemTypes&amp;IncludeSelector=SearchDetails&amp;responseencoding=XML
  </code></pre>
  
  <p>My question is what am I missing to make this simple search call?</p>