use array.splice to delete cartItem
update function to delete categoryList
update index.html
modify the name of categoryCtrl
add button to categoryManager.html
modify previous payCtrl
add total money function to cartCtrl
modify the pay.html
add categoryCtrl
add categoryService.js
add goodsInformationService.js
add goodsInformationManager.js to controllers
change the name of goodsInformationManagerCtrl to GoodsInformationCtrl
update the goodsInformationService
modify the ng-repeat in goodsInformation.html
update route in app.js
add function to add category
update addCategory function in categoryService
add addCategory.html
add modifyCategory.html