added code39 extended mode decode hint

[dalferth]

The Code39Reader has an extendedMode Option. With my enhancement you can now enable the extendedMode like other features via decode hints.

Example:

const hints = new Map();

hints.set(DecodeHintType.POSSIBLE_FORMATS, [BarcodeFormat.CODE_39]);
hints.set(DecodeHintType.ENABLE_CODE_39_EXTENDED_MODE, true);

const codeReader = new BrowserMultiFormatReader(hints);

[ollejernstrom]

Nice!

This feature will solve a lot of issues people are having with scanning Code39. IMO this should even be the default since Code39 is a subset of Code39Extended

[werthdavid]

Thanks!