Read stored json with default UTF-8 encoding

[schnapster]

No description provided.

[baranowb]

@schnapster - could you please create a ticket for this PR? Also, what about UTF-16/32 This change will lock it to UTF-8 which is fine for most. Would be great to have defalt and ability to configure.

[schnapster]

@baranowb for UTF-16/32, the user can simply provide a charset in the header. have a look a few lines above the code I added, it always respects the charset parameter from the header first before deciding for defaults for specific content-types.

As for the ticket - I'm not that deeply involved with the project and its details. To avoid back-and-forthing through a bespoke bureaucracy process and guidelines, please feel free to do all the required steps on my behalf, including formatting/renaming of code if necessary. "Allow edits by maintainers" is enabled =) I'd be happy sign a CLA if necessary.

Best,
Dennis