Update to 3.0220
    
    - New upstream release 3.0220
      - Add comprehensive JSON decode spectests from
        http://seriot.ch/parsing_json.html (GH#72)
      - Decode with BOM (UTF-8, UTF-16, or UTF-32); for now only UTF-8, the others
        error
      - Fixed detection of final \0 as illegal non-whitespace garbage; fixes
        spectest 'n_number_then_00' (GH#72)
      - Changed decode of unicode noncharacters between U+FFFD and U+10FFFF to the
        recommended U+FFFD REPLACEMENT CHARACTER, when not in the binary or relaxed
        mode