参考:
http://baike.baidu.com/link?url=srEJdlfUv4vrTTZ_IK2RbcGqtA8hCEuvNLNoAuk06fep9UbXuSy84J7-Q3FhCj4PDOKRb2JdBhruN5PVw81C5K
http://zhidao.baidu.com/link?url=yJDKrHGYB08mqJaEg3tucIDTnss8tAqISadTP5oQd1ZgTqvi8XC9Xiy1app9dMXwBvNi5GCmnRsRapZkctYrhq
http://stackoverflow.com/questions/2107484/what-is-the-difference-between-ga-rc-and-m2-release