Fix reading single-byte characters encoded using \u by libjson. Also fix behavior on code points above UINT16_MAX.
Fix reading single-byte characters encoded using \u by libjson. Also fix behavior on code points above UINT16_MAX.

When libjson encounters an unprintable character, such as 0x02 (the "bold"
toggle character on IRC), it encodes it using \uXXXX. This makes for valid
single-byte-per-character encodings, which were not allowed by the
implementation from commit f0928b8. The implementation has been modified to
allow this.

dazeus/dazeus-core,dazeus/dazeus-core,dazeus/dazeus-core,dazeus/dazeus-core