SignUp ok; gravator ok; login ok;
Merge branch 'master' of https://github.com/CloudEDU/CloudEDUClient

Conflicts:
	CloudEDU/CloudEDU/Common/AppDictionary.xaml
	CloudEDU/CloudEDU/Common/Constants.cs
	CloudEDU/CloudEDU/CourseStore/CategoryForNewest.xaml.cs
	CloudEDU/CloudEDU/CourseStore/MyCourses.xaml.cs
	CloudEDU/CloudEDU/Login/Login.xaml.cs
	CloudEDU/CloudEDU/Login/LoginDictionary.xaml
sqlite ；User 扩展
Merge branch 'master' of https://github.com/CloudEDU/CloudEDUClient

Conflicts:
	CloudEDU/CloudEDU/CourseStore/Coursing.xaml.cs
	CloudEDU/CloudEDU/CourseStore/MyCourses.xaml.cs
	CloudEDU/CloudEDU/Login/Login.xaml.cs