Issue #33: Ski Renting
- added a user to seed data
- added better email validation to customer: email must have a dot and a @ toke
- added tests for email validation
Issue #33: Login System
- styled password and password_confirmation input fields signin and signup form
Issue #33: Login System
- some view refactoring: now using a partial for user list in customer/index (used the fancy variable render way)
- added admin attribute to user model
- added second user to seed data, now one user is admin and one is not admin