Merge pull request #87 from pandamicro/v3_assets_manager

Issue #5892: Polish AssetsManager for win32
fix the bug that delete doesn't work on desktop
Update plugin-x
Merge pull request #88 from joshuastray/fix_delete

fix the bug that delete doesn't work on desktop
Update plugin-x ref
Update plugin-x
Update cocos2dx_files.json
Issue #5970: Catch up bug fixes in Cocos2d-x 3.3
Issue #5970: Fix EditBox bug on iOS8
Issue #5970: Update cocos2dx_files.json