DEMO_Letao2:deal with size

Android屏幕的适配 :
http://neosdong.github.io/program/2014/10/09/Android%E5%B1%8F%E5%B9%95%E
7%9A%84%E9%80%82%E9%85%8D/
DEOM_Letao2:add list view