Custom error backend does not set content-type correctly

[foxylion]

When adding a custom error backend which also provides responses for X-Format=json the nginx does not set the Content-Type header correclty (it's actually text/html).

I think the best case could be that nginx is passing all headers from the error backend to the client. So the error backend can set any Content-Type (and additional headers). (Currently nginx just ignores the headers)

[aledbf]

@foxylion fixed in #275. Please reopen if you still have issues.
Fix included in next release #303

[foxylion]

@aledbf I did also review the pull request #275 but could not find an evidence that this is now fixed. Can you guide me to the change which fixes this (I'm just curious 😃).

[foxylion]

With the new release, I can confirm, this is working.
Thanks for the fix!