增加下拉刷新自定义控件，重构数据库相关类
Merge branch 'master' into usavich

Conflicts:
	src/cn/edu/zju/isst/ui/contact/ContactFilterActivity.java
	src/cn/edu/zju/isst/ui/contact/ContactListFragment.java
	src/cn/edu/zju/isst/ui/contact/NoteBookadapter.java