add admin/products
add admin prodcuts to routes
add product model
db:migrate
add new&show method in controller
add index
add devise Gem and add auth
add bootstrap  gem
add carrierwave Gem and mini_magick Gem
image upload and navigation layout
add gitignore -- config/image
增加前台畫面
delete images
add admin/product destory function
modify show page
alter table  price and quantity column
add price column to product
refactor simple_form_for ui and resize image size
add font awesome