namespace from cocos2d to cc for plugin.
issue #2428: cocos2d --> cc for mm files in engine.
issue #2428: cocos2d --> cc for extensions.
issue #2428: cocos2d --> cc for mm files in samples.
issue #2428: cocos2d --> cc for mm files in templates.
issue #2428: cocos2d --> cc for luabinding.
issue #2428: More logs for travis-ci script.