use capybara-webkit for javascript test

- use it back after being broken on qt4.8
refactor hotel model
refactor room_type model
refactor reservation model
correct reservation controller spec
move authorize_hotel to application controller
fix reservation cucumber tests
refactor specs

- hotel spec
- room spec
update gems
not watch schema any more
fix cucumber test: require haml-rails in features/env.rb
user manage check ins