Update JSON::Tiny to latest from moritz/json

This brings panda's bundled JSON::Tiny up to the latest from moritz/json, including my changes today and a few older ones that had not been grabbed yet.  Note that since you can't panda-install moritz/json without confusing panda terribly (it will start complaining about out of date prereq), this is the only way to get an installable update to the JSON code.