title: Am I using correctly the requestImageForRequest at DFImageManager?
body: <p>I'm using a lib called <code>DFImageManager</code>, and I'm not quite sure I'm going with it the right way.</p>
  
  <p>I was led to believe that within the completion block of <code>requestImageForRequest</code> the <code>info</code> can be used to detect if the request was a success.</p>
  
  <p>However, 10% of the time the <code>info</code> is <code>nil</code> but the <code>image</code> has a value.</p>
  
  <p>What the <code>info</code> param is for? When the <code>info</code> is <code>nil</code>, can I still use the value of <code>image</code>?</p>
  
  <pre><code>DFImageRequestOptions *options = [[DFImageRequestOptions alloc] init];
  options.expirationAge = 60;
  
  DFImageRequest *request = [DFImageRequest requestWithResource:[NSURL URLWithString:imageURL] targetSize:imageView.frame.size contentMode:DFImageContentModeAspectFill options:options];
  
  [[DFImageManager sharedManager] requestImageForRequest:request completion:^(UIImage *image, NSDictionary *info) {
  
          if (info != nil) {
  
              [imageView setImage:image];
          }
          else {
  
              // use a placeholder
          }
  }];
  </code></pre>