optimise tag code
Merge branch 'master' into 652_tag_improvements
update oj, multi_json
json/oj cleanup, see #656
Merge pull request #654 from flapjack/652_tag_improvements

optimise tag code
Merge branch 'master' into 656_fix_oj_errors
Merge pull request #658 from flapjack/656_fix_oj_errors

Fix oj errors
manually merge in master
update diner pact