title: AFNetworking response failure block is called instead of success block
body: <p>AFNetworking response <code>failure</code> block is being called when I get status code 200. How can I make the <code>success</code> be called instead?</p>
  
  <pre><code>AFHTTPRequestOperationManager *manager = [AFHTTPRequestOperationManager manager];
  [manager GET:@"http://128.199.94.58/test/bt/client_token.php" parameters:nil
       success:^(AFHTTPRequestOperation *operation, id responseObject) {
           self.clientToken = responseObject[@"customerID"];
           NSLog(@"Client Token received.");
       }
       failure:^(AFHTTPRequestOperation *operation, NSError *error) {
           // Handle failure communicating with your server
           NSLog(@"Client Token request failed.%@",operation.responseString);
           NSLog(@"error code %ld",(long)[operation.response statusCode]);
       }];
  </code></pre>