Merge pull request #6590 from dumganhar/v3

Re-adds download-deps.py, comments unzip functionality, please help to test the download functionality. Thanks.
[AUTO][ci skip]: updating cocos2dx_files.json
Merge pull request #6591 from CocosRobot/update_cocosfiles_1399375244

[AUTO][ci skip]: updating cocos2dx_files.json