[change] removed unsafe userdata pointer, added safe userValue
[fix] dofile / dostream performs unexpected way in a class function (root table should be used)
[fix] dofile now returns script file's return value correctly
[refactor] nit-ifying test code
[refactor] First attempt to cleanup cocos-test codes
[refactor] renamed ugly c++-lish named literals
[add] Introduced new :> operator which means with-ref to remove confusing 'with expr' and 'with {}' usage
[add] Introduced 'by' keyword syntax sugar for calling with a closure definition (like ruby's 'do')