anchor.diff:  a|
   <1> Optional array containing elements defined by Files Elements sub-section.
   <2> Required string containing output identifier.
  -<3> Required string containing IANA Media type of file.
  +<3> Optional string containing IANA Media type of file.
   <4> Required string containing glob expression for file capture. Executor† is expected to
   capture output relative to OUTPUT_DIR.
   <5> Optional boolean indicating whether a single or multiple values are supported. The executor† is expected to
  
positive.code:     "files": [ // <1>
          {
              "name": "INPUT_FILE", // <2>
              "mediaType": [ "image/x-hdf5-image" ], // <3>
              "multiple": false, // <4>
              "required": true // <5>
          },
  
negative.code: the environment variable name that will be injected by the executor† for job consumption. Refer to
  <<variable-injection>> for details on environment variable available at execution time.
  
  |`mediaTypes`
  |Optional
  2+|MUST be an array of strings that MUST indicate the IANA Media types that the job accepts. If omitted, executor† will
  not be able to perform validation.
  
  |`multiple`
  |Optional
  