Move serialize logic into utility class, and add more loops to handle all types.
Fix file name to the same with class.
Move simple value to the first if case.
Class name consistence.
Fix part code file name.
Fix wrong class name.
Add get variable type util function.
Add more logs.
Fix drive upload function, to handle both insert & update case.
Add utility functions.
Fix wrong constructor.
Add CartPostAttachment class.
Adjust lib order.