Extjs 4 Config和Mixins
http://kldn.iteye.com/blog/1386622
http://www.fengfly.com/html/JavaScript/ExtJs/guanfangjiaocheng/
http://www.sencha.com/forum/showthread.php?267452
http://stackoverflow.com/questions/9261458/where-should-i-define-global-functions-in-extjs-4-mvc/9277950#9277950