title: Send attachment to QuickBlox IOS sdk
body: <p>I have downloaded the quickblox sample chat application and sending text messages are working fine. But how to send attachment like picture, video or else?</p>
  
  <p>According to Quickblox's documentation.
  There is class named <strong>QBChatAttachment</strong> having properties as <strong>type</strong>, <strong>url</strong> and <strong>id</strong> but how to attach files like picture, video or else?</p>