Each additional property must conform to the following schema
    Type: enum (of string)
    
    Must be one of:
    - "UTF-8"
 - "GB2312"
 - "HZ-GB-2312"
 - "CP1361"
 - "BIG5"
 - "BIG5HKSCS"
 - "CP037"
 - "CP273"
 - "CP424"
 - "CP437"
 - "CP500"
 - "CP775"
 - "CP850"
 - "CP852"
 - "CP855"
 - "CP857"
 - "CP858"
 - "CP860"
 - "CP861"
 - "CP862"
 - "CP863"
 - "CP864"
 - "CP865"
 - "CP866"
 - "CP869"
 - "CP932"
 - "CP949"
 - "CP950"
 - "CP1026"
 - "CP1125"
 - "CP1140"
 - "CP1250"
 - "CP1251"
 - "CP1252"
 - "CP1253"
 - "CP1254"
 - "CP1255"
 - "CP1256"
 - "CP1257"
 - "CP1258"
 - "EUC_JIS_2004"
 - "EUC_JISX0213"
 - "EUC_JP"
 - "EUC_KR"
 - "GB18030"
 - "GBK"
 - "HZ"
 - "ISO2022_JP"
 - "ISO2022_JP_1"
 - "ISO2022_JP_2"
 - "ISO2022_JP_2004"
 - "ISO2022_JP_3"
 - "ISO2022_JP_EXT"
 - "ISO2022_KR"
 - "ISO8859_1"
 - "ISO8859_2"
 - "ISO8859_3"
 - "ISO8859_4"
 - "ISO8859_5"
 - "ISO8859_6"
 - "ISO8859_7"
 - "ISO8859_8"
 - "ISO8859_9"
 - "ISO8859_10"
 - "ISO8859_11"
 - "ISO8859_13"
 - "ISO8859_14"
 - "ISO8859_15"
 - "ISO8859_16"
 - "JOHAB"
 - "KOI8_R"
 - "KZ1048"
 - "LATIN_1"
 - "MAC_CYRILLIC"
 - "MAC_GREEK"
 - "MAC_ICELAND"
 - "MAC_LATIN2"
 - "MAC_ROMAN"
 - "MAC_TURKISH"
 - "PTCP154"
 - "SHIFT_JIS"
 - "SHIFT_JIS_2004"
 - "SHIFT_JISX0213"
 - "TIS_620"
 - "UTF_16"
 - "UTF_16_BE"
 - "UTF_16_LE"