added new sections to contents

readme.md

@@ -4,11 +4,13 @@
 
 - [Abstract](#abstract)
 - [Feature set](#feature-set)
+
   - [Classroom](#classroom)
     - [Assigment list](#a-list-of-assignments)
     - [Classpapers](#a-list-of-class-documents)
     - [Teacher chat](#teacher-chat)
   - [Quiz](#quiz)
+
     - [Question types](#question-types)
       - [Text input](#text-input)
       - [Basic select](#basic-select)
@@ -16,6 +18,9 @@
       - [Pair match](#pair-match)
       - [Ordering](#ordering)
       - [File upload](#file-uploads)
+
+  - [Roles](#role)
+
 - [Frontend](#frontend)
   - [Themes](#themes)
 - [Server](#server)
@@ -23,6 +28,7 @@
   - [Backend](#backend)
   - [Authentication](#authentication)
   - [Data storage](#data-storage)
+  - [Database](#database)
   - [Load balancing](#load-balancing)
 
 - [Documentation](#documentation)