Application/json body request with an extended content-type header (charset) should not be coerced

[ebourmalo]

The initial check to turn off the coercion of the request body when the header is application/json was:

ctx.req.get('content-type') === 'application/json'

If the content-type header is extended with the charset definition (i.e application/json;charset=UTF-8), the body is coerced and that is NOT what we want :)

Here is the PR for a fix, updating the check for allowing this use case: #266

[STRML]

Never mind, I see this is different than #264 - good patch, 👍.