issue #5281: asset manager compiling issue
Merge pull request #33 from joshuastray/v3_assets_manager

issue #5281: asset manager compiling issue
issue #5281: add assetsmanager files
Merge pull request #34 from joshuastray/v3_assets_manager

issue #5281: add assetsmanager files
Feature #4977: Add CCEventListenerAssetsManager.h to cocos-ext.h
Merge branch 'v3_assets_manager' of git://github.com/cocos2d-html5/cocos2d-x into v3_assets_manager