- merge with JSON-XS-3.02:
  - docs: add some INTEROP, stricter nonref RFC 7159 and
          TAGGED VALUE SYNTAX AND STANDARD JSON EN/DECODERS paragraphs
  - use 7159 nonref detection from JSON-XS: json_nonref()
  - add some SAVESTACK_POS calls
  - add -f cbor decode option (via CBOR::XS) to cpanel_json_xs

- fixed many spelling errors in the new docs
- fixed errors with threaded perls
- fixed code quality in the merged code, and
  new warnings found with gcc-5

- add -f and -t yaml-xs and yaml-syck options to cpanel_json_xs