Safe JSON

This repository contains a fork of the encoding/json package from Go 1.6.

The following changes were made:

Object deserialization uses case-sensitive member name matching instead of case-insensitive matching. This is to avoid differences in the interpretation of JOSE messages between go-jose and libraries written in other languages.
When deserializing a JSON object, we check for duplicate keys and reject the input whenever we detect a duplicate. Rather than trying to work with malformed data, we prefer to reject it right away.