anchor.diff:  
   ### Tip (TipWithoutId)
   + id: `12345678-9012-3456-7890-123456789012` (string, required) - tip UUID, 36 chars, 8-4-4-4-12 chars
  ++ essenceImageURL: `http://www.sourcecertain.com/img/Example.png` (string, optional) - URL to image attached to this flashcard
   
   ### TagWithoutId (object)
   + name: `Sample tag name` (string) - name attribute for Tag
  
positive.code:         AAAAAAAAAAAAAAAAAAAAAP/EABQRAQAAAAAAAAAAAAAAAAAAAAD/2gAMAwEAAhEDEQA/AL+AD//Z
          -----BOUNDARY
  
  
  
  # Group Tip
  
  
negative.code: + Response 200 (application/json)
  
      This response is returned when tip was updated.
      
      + Attributes (Tip)
      
  ### Add image as essence [POST /decks/{deckId}/flashcards/{flashcardId}/tips/{tipId}/essenceImage]
  
  + Request (multipart/form-data; boundary=---BOUNDARY)
  
          -----BOUNDARY
          Content-Disposition: form-data; name="file"; filename="image.jpg"
          Content-Type: image/jpeg
          Content-Transfer-Encoding: base64
  
          /9j/4AAQSkZJRgABAQEAYABgAAD/2wBDAAgGBgcGBQgHBwcJCQgKDBQNDAsLDBkSEw8UHRofHh0a
          HBwgJC4nICIsIxwcKDcpLDAxNDQ0Hyc5PTgyPC4zNDL/2wBDAQkJCQwLDBgNDRgyIRwhMjIyMjIy
          MjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjL/wAARCAABAAEDASIA
          AhEBAxEB/8QAFQABAQAAAAAAAAAAAAAAAAAAAAf/xAAUEAEAAAAAAAAAAAAAAAAAAAAA/8QAFAEB
          AAAAAAAAAAAAAAAAAAAAAP/EABQRAQAAAAAAAAAAAAAAAAAAAAD/2gAMAwEAAhEDEQA/AL+AD//Z
          -----BOUNDARY
  
  + Response 200 (application/json)
  
      This response is returned when essence image was added.
      
      + Attributes (Tip)
  
  