Local file reader does not correctly read UTF8-BOM

[jheeffer]

Take a dataset and save one of its files as UTF8-BOM (instead of normal UTF8) and see how DDFcsv reader (the one shipped with Gapminder Tools Offline 4.0.0) fails.

[jheeffer]

utf8bom_testcase.zip

ddf--entities--countryy.csv is a UTF8-BOM file which causes it to return null for country values.
save as UTF8 (without BOM) and problem is gone.

{
  "name": "reader/error/keyColumnMissingInReaderResult",
  "message": "Reader result: Key column 'countryy' is missing from 'entities' response",
  "details": "countryy",
  "ddfql": {
    "language": "en",
    "from": "entities",
    "animatable": "time",
    "gapfill": true,
    "select": {
      "key": [
        "countryy"
      ],
      "value": [
        "name",
        "rank",
        "shape_lores_svg"
      ]
    },
    "where": {},
    "join": {},
    "order_by": [
      "rank"
    ]
  },
  "browserDetails": "Electron Chrome 61 (61.0.3163.100)",
  "osName": "Windows 10",
  "homepoint": "file:///C:/Users/Jasper%20Heeffer/Gapminder%20Offline/resources/app.asar/dist/index.html#/",
  "time": "Wed Oct 17 2018 23:26:23 GMT+0200 (W. Europe Daylight Time)"
}