[TIMOB-23623] iOS: Ti.setUserAgent() doesn't exist

   Ti.API.warn(Ti.getUserAgent());
   
   Ti.UI.createWindow().open();
   
   // 1 ---- Use the default Appc user agent
   
   var url = "http://hans-knoechel.de/ua.php";
   var client = Ti.Network.createHTTPClient({
   	// function called when the response data is available
   	onload : function(e) {
   		Ti.API.info("First request completed");
   		Ti.API.info("Received text: " + this.responseText);
   		
   		// 2 ---- This time, set the Ti.userAgent manually.
   		
   		Ti.setUserAgent("my-custom-user-agent");
   		Ti.API.warn(Ti.getUserAgent());
   		
   		var url2 = "http://hans-knoechel.de/ua.php";
   		var client2 = Ti.Network.createHTTPClient({
   			// function called when the response data is available
   			onload : function(e) {
   				Ti.API.info("Second request completed");
   				Ti.API.info("Received text: " + this.responseText);
   				
   				var url3 = "http://hans-knoechel.de/ua.php";
   				var client3 = Ti.Network.createHTTPClient({
   					// function called when the response data is available
   					onload : function(e) {
   						Ti.API.info("Third request completed");
   						Ti.API.info("Received text: " + this.responseText);
   					},
   					// function called when an error occurs, including a timeout
   					onerror : function(e) {
   						Ti.API.debug(e.error);
   						alert('error');
   					},
   					timeout : 5000  // in milliseconds
   				});
   				// Prepare the connection.
   				client3.open("GET", url3);
   				
   				// 3 ---- This time, override the request header inside the http client (highist prio)
   				client3.setRequestHeader('User-Agent', 'another-user-agent');
   
   				// Send the request.
   				client3.send();	
   				
   			},
   			// function called when an error occurs, including a timeout
   			onerror : function(e) {
   				Ti.API.debug(e.error);
   				alert('error');
   			},
   			timeout : 5000  // in milliseconds
   		});
   		// Prepare the connection.
   		client2.open("GET", url2);
   		// Send the request.
   		client2.send();	
   	},
   	// function called when an error occurs, including a timeout
   	onerror : function(e) {
   		Ti.API.debug(e.error);
   		alert('error');
   	},
   	timeout : 5000  // in milliseconds
   });
   
   // Prepare the connection.
   client.open("GET", url);
   // Send the request.
   client.send();