android 6.0的问题

打包的时候，targetsdkversion尽量设置为22，这样权限问题会少很多

参考文章：

http://unclechen.github.io/2016/03/06/Android6.0%E6%9D%83%E9%99%90%E9%80%82%E9%85%8D%E4%B9%8BSD%E5%8D%A1%E5%86%99%E5%85%A5/

http://bxbxbai.github.io/2016/05/27/android-runtime-permission/

https://inthecheesefactory.com/blog/things-you-need-to-know-about-android-m-permission-developer-edition

https://code.google.com/p/android/issues/detail?id=197287