anchor.diff:    + per_page (optional, integer) ... number of items to include on a page default is 20
     + project_id (optional, integer) ... project_id to see contents for
     + language (optional, string) ... language code to search for
  -  + include (optional, string) ... comma seperated list of linked resources to load
  +  + include (optional, string) ... comma separated list of linked resources to load
   
   + Request
   
  
positive.code:     [ProjectContent][]
  
  ### Destroy a ProjectConent [DELETE]
  Only users who edit premissions for the parent project may remove
  project content models.
  
  Project Contents that have the same language as their parent project's
  
negative.code:   + sort (optional, string) ... field to sort by
    + user_id (optional, integer) ... user_id to see preferences for
    + collection_id (optional, integer) ... collection_id to see preferences for
    + include (optional, string) ... comma separated list of linked resources to load
  
  + Request
  
  