Fix tests for JSON

[perlpunk]

See #68

• Remove in-json for tests which have null keys
• Remove in-json for tests which have non-standard tags
• Convert numeric keys into string keys so that JSON tests pass
• Add SQY9 as a copy of UGM3 without the non-standard tag

[perlpunk]

@ingydotnet I created #72 Will take care of the rest by adding new tags.