basic login
add methods like currentUser in ApplicationController
modifiction on application_controller: refresh exp_time
forget to add files
small bug on first visit index
Merge pull request #1 from KevinXuxuxu/feature/login

Feature/login
altered article with user loged in
generated personal page
Merge branch 'feature/message' of github.com:KevinXuxuxu/XuetangProject into feature/personal_page
added view with message display to personal
altered behaviours of messages