Administrators can now delete or update orders from the manage orders tab

...du/drexel/TrainDemo/controllers/sales/CartController.java

...u/drexel/TrainDemo/controllers/sales/OrderController.java

src/main/java/edu/drexel/TrainDemo/models/sales/Order.java

...ava/edu/drexel/TrainDemo/services/sales/OrderService.java

...edu/drexel/TrainDemo/services/sales/OrderServiceImpl.java

src/main/resources/static/js/admin.js

src/main/resources/templates/admin/orders.html