use better_errors gem
use activeadmin gem
create a user admin page
[FIX] wrong imagemagick path in mac/linux platform
set the display text of html option tag for the prize model
set the display text of html option tag for the mall model
update activeadmin css style
create a provider admin page
create a mall admin page
[FIX] can't update profile without entering password
make icon to be viewable
use capybara gem
setup Capybara
create rspec test: admin mall
define a admin user factory
admin_mall#index request test: login success/fail
define a mall fixture in Factory
defined a random mall data factory
defined random mall with random valid/wrong/empty icon/banner factories
admin_mall#new request test: create mall with empty data