Use Exchange publish in objc tutorial 2

[#116890463]

Author: camelpunch

objective-c/tutorial2/Cartfile.resolved

@@ -1,3 +1,3 @@
 github "robbiehanson/CocoaAsyncSocket" "562bae6af6dbd7e1891293dae20b9f79a2fd7228"
 github "Mantle/Mantle" "a16d18f635b3ba1ffb01d27d4393ee97cadf4f34"
-git "/Users/pivotal/workspace/rabbitmq-objc-client" "47192a8946b49e813da98c5f316e22d457e9a132"
+git "/Users/pivotal/workspace/rabbitmq-objc-client" "7c75c54a1f36265e3c089a7e8cbc1c1876ab06ea"

objective-c/tutorial2/tutorial2/ViewController.m

@@ -26,7 +26,7 @@ - (void)newTask:(NSString *)msg {
 
  RMQQueue *q = [ch queue:@"task_queue" options:RMQQueueDeclareDurable];
 
- [q publish:msg];
+ [ch.defaultExchange publish:msg routingKey:q.name];
  NSLog(@"Sent %@", msg);
 
  [conn close];