Restructured front end code into components and pages
Components should be as dumb and generic as possible. Pages should dispatch actions, pass props to components etc,
Student page now gets submission and submissiontyp from api and displays those to the student
Added information which submissions have been viewed

If the user now accidentally presses reload, the relevant session state (token, etc. ) will be retrieved from the session storage.

The JWT Token is now refreshed upon each route change. If the token is expired the user will be logged out and redirected to the login page.

Implemented version of the student-page using vuetify and the new general layout. The side navigation should be displaying links to the (not yet implemented) detail views of the submissions to provide easy way to change between submission views.

Added BaseLayout component that will serve as bas for the layout of the app. It is modeled after https://next.vuetifyjs.com/examples/layouts/google-contacts . The gradySpeak has been moved to the front-end.

closes #65
closes #59

Started work on using a store for the submission-notes component

google-code-prettify and font-awesome are no longer part of the repo but instead loaded via npm/yarn

Started work on structuring the vuex store into modules

To access the prototype run yarn start and go to /notes/

* no url configuration needed simply register viewset with router
* now using DefaultRouter, meaning api root is now browsable
* merged some views
* makes it easier to include api schema later
* Ran isort and updated docstring

Changed package.json mian.js App.vue accordingly. StudentPage Components need updating.

Backend
- Added isStudent permission
- Added serializers apropriate for StudentPage
- Added api-endpoint urls
- Added views regarding StudentPage
- Migrated the Django Session Authentication to djangorestframework-jwt authentication

Frontend
- Migrated from vue-resource to axios because of better documentation & features
- Added Login Component
- Added First Part of StudentPage containing overview of exam and subissions

Closes #41
References #39