PGB-API-Testing-v1

Hi Lichuan, this was the v1 of PGB-API-Testing test cases. If there were something wrong, please tell me and I'll do my best to fix them. Thanks. 

Note:
1,  The app ID and Collaborator ID need to be filled in the code manually. 

Issues:
1,  Changing '/me' 's username can not find page.
2,  Post method and Put method not work with '/apps/:id/icon'
3,  Can not handle with the "Error: ENOENT" at testapi_settings.js