Merge pull request #94 from Jael/master

add the default user_image
modify question_controller
remove sth unnecessary in question
Merge pull request #95 from caok/master

Improve the questions controller
added assets for heroku
remove assets
Fixed the rspec test
Merge pull request #96 from hlee/master

Fixed rspec fail about question
accept answer beta
fix the redirect path
fix the redirect path of the cancan