Approves or rejects the request

[mvgame74]

Client->Controller: "Post approval/denial for a listing"
Controller->Model: "Notify user whether requests have been approved/denied and update database"
Model->Controller: "Notification has been sent and database updated"
Controller->View: "Requests the request page"
View->Controller: "Posts the request page"
Controller->Client: "Displays the request page(again)"