add a migration for user_settings
add some specs
add some specs for user_settings
add rules for assisiation between users and user_settings
when signing up users should have their own settings
create a setting if a user does not have it
make SettingsController and add some config for its controller
add some specs for SettingsController
implment setting page
Merge pull request #3 from yucchiy/user-setting

Implement setting page