Fix appointment policy not being called correctly

This commit fixes the appointment policy being called at the wrong time, with the wrong arguments.
It also fixes wrong references on the auth service provider, also fixing other issues with poliy usage.

Fixes #3 and SPACEJEWEL-HOSTING-59.

app/Http/Controllers/AppointmentController.php

@@ -67,7 +67,6 @@ class AppointmentController extends Controller
     public function updateAppointment(Request $request, $applicationID, $status)
     {
 
-      $this->authorize('update', Appointment::class);
 
         $application = Application::find($applicationID);
         $validStatuses = [
@@ -75,6 +74,9 @@ class AppointmentController extends Controller
           'CONCLUDED'
         ];
 
+        $this->authorize('update', $application->appointment);
+
+
 
         if (!is_null($application))
         {