Fix a bug caused by refresh the Home page.
Basically completed sidebar.

Signed-off-by: Xie Haozhe <zjhzxhz@gmail.com>
Complete welcome.php page.
Create a model for students table.

Signed-off-by: Xie Haozhe <zjhzxhz@gmail.com>
Fix a bug that the footer won't fix to bottom in some situations.
Use inline sign in form in support page.

Signed-off-by: Xie Haozhe <zjhzxhz@gmail.com>
Add functions to Users_model in order to make it easier to use.
Fix a bug that if you use a illeagal url, the function load() in the Home class will give you a fatal error.
Initially completed the profile page for students.

Signed-off-by: Xie Haozhe <zjhzxhz@gmail.com>