anchor.diff:  Rokfor is still in early stage, the API might change and will be
   extended for sure.
   
  -# Group Contributions 
  +# Group Contribution 
   
   Contributions are the main elements containing data. 
   They are defined by templates, so the returned json data is
  
positive.code:  
  + Response 200 (application/json)
  
  
  
  
  # Group File
  
negative.code: + Parameters
  
      + contribution: 1 (number) - Id of the contribution.
  
  ### Create Contribution [PUT /api/contribution]
  
  