anchor.diff:  that property.  This allows easy access like `annotations.title[0].property.value` to show
   e.g. a title without having to dig through the list.
   
  +The fields returned in the response can be selected with the `fields` parameter.
  +
  +Some referenced objects can be populated in the response with the `include` parameter.  
  +(However, `fields` have precedence, so if a field is excluded it will not be populated
  +even if `include` says so.)  The fields that can be populated are:
  +
  +- `owner`: either `owner.user` or `owner.org`
  +- `added_by`
  +- `updated_by`
  +
  +TODO: decide if more fields should be allowed to be populated.  The lists can be rather heavy.
  +
  +
   + Parameters
       + workID (string) ... Work record ID
  -    + include (string, optional) ... Which subdocument lists to include in the response objects. 
  -        If omitted or empty, all lists are returned in full.  If `none`, all are omitted.
  -        Otherwise acomma-separated names: `collaborators`, `annotations`, `sources`.
  +    + fields (string, optional) ... Comma-separated list of top-level fields to include
  +        (filtering out all other fields), or exclude (if preceeded by `-`)
  +    + include (string, optional) ... Comma-separated list of subobjects to populate.
       + annotations (string, optional) ... Select properties to get or update.
   
   + Model
  
positive.code:         
  
  
  ### Create a new Media for an existing Work [POST]
  
  Create a new Media instance and link it to the Work.
  
  Only the following properties in the request will be used:
  
  - annotations (empty list if omitted)
  - metadata (empty object if omitted)
  - replaces (null if omitted)
  
  + Request (application/json)
      [Media][]
      
  + Response 201 (application/json)
      [Media][]
  
negative.code: 
  
  
  ## Media [/works/{workID}/media/{mediaID}{?annotations,fields,include}]
  A media instance, which is a read-only record of a particular media instance of a Work
  at the time it was recorded in the catalog.
  
  