Wish feature: json5

[rockeet]

As described in: http://json5.org/
And there is a js implementation for json5: https://github.com/aseemk/json5
But I didn't found a good json5 in C++

[rockeet]

I think the most useful feature is to allowing trailing commas, and this feature is very easy to implement.

[stopiccot]

+1 for trailing commas, I'm full of this nazi parsers

[nlohmann]

I think adding JSON5 support is out of scope of this library. It would require a lot of effort to maintain JSON compliance while offering optional JSON5 support. Furthermore, I do not see a lot of need for JSON5 support.