Added results CRUD and result detailed view

ref-test/admin/models/tests.py

@@ -64,6 +64,10 @@ class Test:
         return test_code.replace('—', '')
     
     def delete(self):
+        test = db.tests.find_one({'_id': self._id})
+        if 'entries' in test:
+            if test['entries']:
+                return jsonify({'error': 'Cannot delete an exam that has entries submitted to it.'}), 400
         if self.dataset is None:
             self.dataset = db.tests.find_one({'_id': self._id})['dataset']
         if db.tests.delete_one({'_id': self._id}):