seperate pagination to pages.html.haml and update css
challenge: some work on checking visitor answers
rspec: update challenge related, and add shortcut methods for factorygirl to
test helper
Spec: update question
application helper rename is_admin? to admin_user?
spec: add test cases for normal_user? in app helper
spec: test_helper update
model: question check_answers add hash key :wrong, update spec
challenge: refine methods for submit answers and show results, And test cases
rspec: fix authentication spec
rm unneccessary spec files and move root to the top of route file
challenge: minor fix
add auto deploy to heroku