add front-end
add front-end
Merge branch 'front-end'

Conflicts:
	app/controllers/application_controller.rb
	app/controllers/home_controller.rb
	app/views/home/index.html.haml
	app/views/layouts/application.html.haml
add front-end search
add user validator
删除thinking文件
把mysql 改为 postgresql
增加 rails_12factor gem
config assets comile false
move config asset precompile
add gem sqlite3
modifed gemfile
删除多余文件
modifed application
modifed admin.html.haml
modifed js
modifed js
modifed js
1.category update 修复 2.article create 页面修改 3. add article 切换franch and chinese id的统一 3. add delete button for article 4. add cancle button 5.remove user email 以及 edit 不需要输入密码
modified article's column chinese_content and franch_content to text