Use XMLPage passthrough mode to speed up and consume less memory for big XML exports.

git-svn-id: http://svn.code.sf.net/p/itop/code/trunk@944 a333f486-631f-4898-b8df-5754b55c2be0

webservices/export.php

@@ -79,7 +79,7 @@ if (!empty($sExpression))
 				break;
 				
 				case 'xml':
-				$oP = new XMLPage("iTop - Export");
+				$oP = new XMLPage("iTop - Export", true /* passthrough */);
 				cmdbAbstractObject::DisplaySetAsXML($oP, $oSet);
 				break;