fix create directory bug on windows
Merge branch 'v3_assets_manager' of git://github.com/cocos2d-html5/cocos2d-x into v3_assets_manager
remove writeablepath
Merge pull request #45 from pandamicro/v3_assets_manager

Feature #4977: Make AssetsManager::batchDownload protected
hide black window on windows
Merge pull request #43 from joshuastray/v3_assets_manager

fix create directory bug on windows
Feature #4977: Avoid compilation error in template project