Update IExtraMetadataWriter.setExtraMetadata(...) to accept an Object

[melissalinkert]

If an ITagProvider is passed to this method when called on DicomWriter, the ITagProvider is directly added to the tag provider list. If a String is passed instead, then it is assumed to be a path to a file that can be parsed by DicomJSONProvider (as before).

Drafting for consideration in 8.0.0. @ebremer, is this sufficient to cover what you had in mind for #4169? If not, concrete suggestions and/or a more complete description of the use case that needs to be considered would be very helpful.

Any writers that implement IExtraMetadataWriter in the future then have flexibility in what they accept in setExtraMetadata(...). I don't know if this ends up being too flexible though.

I did test briefly with this and still got the expected output file contents:

$ cat hierarchy-test.json 
{
   "BodyPartExamined": {
     "Value": "BRAIN",
     "VR": "CS",
     "Tag": "(0018,0015)"
   },
   "SpecimenLabelInImage": {
      "Value": "NO",
      "VR": "CS",
      "Tag": "(0048,0010)",
      "ReplacementStrategy": "IGNORE"
   },
   "ContributingEquipmentSequence": {
     "VR": "SQ",
     "Tag": "(0018,a001)",
     "Sequence": {
       "Manufacturer": {
         "Value": "PixelMed",
         "VR": "LO",
         "Tag": "(0008,0070)"
       },
       "ContributionDateTime": {
         "Value": "20210710234601.105+0000",
         "VR": "DT",
         "Tag": "(0018,a002)"
       }
     }
   },
   "OpticalPathSequence": {
    "VR": "SQ",
    "Tag": "(0048,0105)",
    "Sequence": {
      "IlluminationTypeCodeSequence": {
        "VR": "SQ",
        "Tag": "(0022,0016)",
        "Sequence": {
          "CodeValue": {
            "VR": "SH",
            "Tag": "(0008,0100)",
            "Value": "111743"
          },
          "CodingSchemeDesignator": {
            "VR": "SH",
            "Tag": "(0008,0102)",
            "Value": "DCM"
          },
          "CodeMeaning": {
            "VR": "LO",
            "Tag": "(0008,0104)",
            "Value": "Epifluorescence illumination"
          }
        }
      },
      "IlluminationWaveLength": {
        "VR": "FL",
        "Tag": "(0022,0055)",
        "Value": "488.0"
      },
      "OpticalPathIdentifier": {
        "VR": "SH",
        "Tag": "(0048,0106)",
        "Value": "1"
      },
      "OpticalPathDescription": {
        "VR": "ST",
        "Tag": "(0048,0107)",
        "Value": "replacement channel"
      }
    },
    "ResolutionStrategy": "REPLACE"
   }
}
$ bfconvert -no-upgrade test.fake wednesday-test.dcm -extra-metadata hierarchy-test.json

[ebremer]

It looks good @melissalinkert ! It will allow me to create my own ITagProvider(s). Specifically, one that takes an Apache Jena Model as a constructor parameter. :-)