users_controllerの作成
users#indexのroutesを設定
users#indexの簡単なfriends一覧を作成
Merge pull request #2 from BASASI/feature/users

Feature/users friends一覧
sessions#newにボタン追加
Merge pull request #3 from BASASI/feature/sessions

sessions#newにボタン追加
Add omniauthable (callbacks are not yet implemented)
Create Identity model
Implement some methods for auth
Add omniauth initializer
Add link url to users/sign_up
Add some migration files
認証部分実装