title: QBChatDialog data is not persistent. How do I make QBChatDialog data persistent?
body: <p>I created a QuickBlox QBChatDialog as shown below and in the "successBlock" createdDialog.data is null.</p>
  
  <p>In my QuickBlox account I created Custom Object called "DialogInfo" with a field called "ReadOnly" with type String.</p>
  
  <p>I'm using iOS SDK 2.3</p>
  
  <p>Please tell me how to make QBChatDialog data persistent? I expect the "successBlock" createdDialog.data to not be null.</p>
  
  <pre><code>QBChatDialog *chatDialog = [QBChatDialog new];
  chatDialog.name = @"Chat with Bob, Sam, Garry";
  chatDialog.occupantIDs = @[@(55), @(678), @(22)];
  chatDialog.type = QBChatDialogTypeGroup;
  chatDialog.data = @{@"class_name": @"DialogInfo", @"ReadOnly": @"true"};
  [QBRequest createDialog:chatDialog successBlock:^(QBResponse *response, QBChatDialog *createdDialog) {
  
  } errorBlock:^(QBResponse *response) {
  
  }];
  </code></pre>
  
  <p>++++++++++++++++++++++++++++++++++++++++++++++++++++</p>
  
  <p>Here is debug print of variable createDialog inside successBlock. Notice that data is null.</p>
  
  <pre><code>Printing description of createdDialog:
  
  ID:5593d441535c127af61111e0                      
  Created At:2015-07-01 11:51:29 +0000                      
  Room JID:23266_5593d441535c127af61111e0@muc.chat.quickblox.com                      
  name:Chat with Bob, Sam, Garry                      
  photo:(null)                      
  type:2                      
  lastMessage:(null)                      
  lastMessageDate:(null)                      
  occupantIDs:(
  3874827
  )                      
  userID:3874827                      
  data:(null)                      
  unreadMessagesCount:0                      
  lastMessageUserID:0
  </code></pre>
  
  <p>I expect data to be like:</p>
  
  <pre><code>@{@"class_name": @"DialogInfo", @"ReadOnly": @"true"}
  </code></pre>