Kangaru/BaseApp — pull request #6 by zlw (2011-11-20 18:33:58+00:00)
Title: Sexier user model

### Added timestamps:

- #created_at
- #updated_at

### Set key(#id) to username

```ruby
user = User.create(username: 'johndoe' ...)

user.username #=> "johndoe"
user.id #=> "johndoe"

user.username.should == user.id #=> true
User.find("johndoe").should == user #=> true
```