title: RestKit multiple response descriptors for the same pathPattern
body: <p>Is there a way to define 2 or more response descriptors all having the same <code>pathPattern</code>? My assumption was that they would match not only based on the <code>pathPattern</code>, but also on the <code>method</code>. But apparently that isn't the case.</p>
  
  <p>Here is my object mapping:</p>
  
  <pre><code>RKObjectMapping *commentMapping = [RKObjectMapping mappingForClass:[Comment class]];
  [commentMapping addAttributeMappingsFromArray:@[@"comment", @"rating", @"views", @"venue", @"user_views"]];
  </code></pre>
  
  <p>When I do a GET request, I get a list similar to this:</p>
  
  <pre><code>{
      'meta': {
          'total_objects': 2,
          'limit': 20,
          ...
      },
      'objects': [
           {
               'comment': '...',
               'rating': 3.5,
               ...
           },
           ...
      ]
  }
  </code></pre>
  
  <p>And when I do a POST request to create a new object, I just get back something like this:</p>
  
  <pre><code>{
      'comment': '...',
      'rating': 3.5,
      ...
  }
  </code></pre>
  
  <p>So what I want to do is define two different <code>responseDescriptor</code>s -- one for each request method. So this is what I did:</p>
  
  <pre><code>[objectManager addResponseDescriptor:[RKResponseDescriptor responseDescriptorWithMapping:commentMapping
                                                                                    method:RKRequestMethodGET
                                                                               pathPattern:@"comment/"
                                                                                   keyPath:@"objects"
                                                                               statusCodes:RKStatusCodeIndexSetForClass(RKStatusCodeClassSuccessful)]];
  
  [objectManager addResponseDescriptor:[RKResponseDescriptor responseDescriptorWithMapping:commentMapping
                                                                                    method:RKRequestMethodPOST
                                                                               pathPattern:@"comment/"
                                                                                   keyPath:nil
                                                                               statusCodes:RKStatusCodeIndexSetForClass(RKStatusCodeClassSuccessful)]];
  </code></pre>
  
  <p>The problem is, the second one (the one with a <code>nil</code> <code>keyPath</code>) is always used. Even for GET requests. Which really messes things up.</p>
  
  <p>What am I doing wrong? Or is there even any way to do what I want here?</p>