allow metadata field names

Here are all of the allowed metadata fields that will be extracted from the inputted MARC record and included in the metadata block of the outputted IIIF record. The key of key key:value pair is the MARC field, the value of the key:value pair is the label that will appear in the metadata block.

When editing metadata fields, you must use the appropriate label as defined below. The library will not recognize any other field name.

{
    "250": "Edition Statement",
    "254": "Musical Presentation Statement",
    "255": "Cartographic Mathemtical Data",
    "256": "Computer File Characteristic",
    "257": "Country of Producing Entity",
    "258": "Philatelic Issue Data",
    "260": "Publication, Distribution, etc (Imprint)",
    "263": "Projected Publication Date",
    "264": "Production, Publication, Publication, Distribution, Manufacture, and Copyright Notice",
    "270": "Address",
    "600": "Subject Added Entry - Personal Name",
    "610": "Subject Added Entry - Corporate Name",
    "611": "Subject Added Entry - Meeting Name",
    "630": "Subject Added Entry - Uniform Title",
    "647": "Subject Added Entry - Named Event",
    "648": "Subject Added Entry - Chronological Term",
    "650": "Subject Added Entry = Topical Term",
    "651": "Subject Added Entry - Geographic Name",
    "653": "Index Term - Uncontrolled",
    "654": "Subject Added Entry - Faceted Topical Term",
    "655": "Index Term - Genre/Form",
    "656": "Index Term - Occupation",
    "657": "Index Term - Function",
    "658": "Index Term - Curriculum Objective",
    "662": "Subject Added Entry - Hierarchical Place Name",
    "690": "Local Subject",
    "691": "Local Subject",
    "692": "Local Subject",
    "693": "Local Subject",
    "694": "Local Subject",
    "695": "Local Subject",
    "696": "Local Subject",
    "697": "Local Subject",
    "698": "Local Subject",
    "699": "Local Subject",
    "700": "Added Entry - Personal Name",
    "710": "Added Entry - Corporate Name",
    "711": "Added Entry - Meeting Name",
    "720": "Added Entry - Uncontrolled Name",
    "730": "Added Entry - Uniform Title",
    "740": "Added Entry - Uncontrolled Related/Analytical Title",
    "751": "Added Entry - Geographic Name",
    "752": "Added Entry - Hierarchical Place Name",
    "753": "System Details Access to Computer File",
    "754": "Added Entry - Taxonomic Identification",
    "758": "Resource Identifier",
    "760": "Main Entry Series Entry",
    "762": "Subseries Entry",
    "765": "Original Language Entry",
    "767": "Translation Entry",
    "770": "Supplement/Special Issue Entry",
    "772": "Supplement Parent Entry",
    "773": "Host Item Entry",
    "774": "Constituent Unit Entry",
    "775": "Other Edition Entry",
    "776": "Additional Physical Form Entry",
    "777": "Issued With Entry",
    "780": "Preceding Entry",
    "785": "Succeeding Entry",
    "786": "Date Source Entry",
    "787": "Other Relationship Entry",
    "800": "Series Added Entry - Personal Name",
    "810": "Series Added Entry - Corporate Name",
    "811": "Series Added Entry - Meeting Name",
    "830": "Series Added Entry - Uniform Title",
    "841": "Holdings Coded Data Values",
    "842": "Textual Physical form Designator",
    "843": "Reproduction Note",
    "844": "Name of Unit",
    "845": "Terms Governing Use and Reproduction",
    "850": "Holding Institution",
    "852": "Location",
    "853": "Captions and Pattern - Basic Bibliographic Unit",
    "854": "Captions and Pattern - Supplementary Material",
    "855": "Captions and Pattern - Indexes",
    "856": "Electronic Location and Access",
    "863": "Enumeration and Chronology- Basic Bibligraphic Unit",
    "864": "Enumeration and Chronology - Supplementary MAterial",
    "865": "Enumeration and Chronology - Indexes",
    "866": "Textual Holdings - Basic Bibliographic Unit",
    "867": "Textual Holdings - Supplementary Material",
    "868": "Textual Holdings - Indexes",
}