Resolves: GREG-200

Removed and introduced some borders. Added some text. Increased the size
of icons.

Resolves: GREG-142

Overview buttons now have black text. Sponsor menu arrows are now black.
Links in footer has white underline on hover, otherwise nothing.

Resolves: GREG-15

Styling now matches the figma sketches

All A and AA problems have been fixed except a missing label on an input
field.

Move the height/width settings to the logo component

Code for guest routes moved to their own folder so that we don't need
multiple api calls.
Serializer class for roles has been simplified with methods for
validation of each field and a separate one used in invites without
requiring the person field.

Resolves: GREG-61

Allows changes to start- and end date for guest roles. A new endpoint
has been added to the ui api for doing PATCH request to support this.
The max days of each role type is respected.

Resolves: GREG-83

Issue: GREG-72

- Only clear info on 401
- Move the fetch to the provider.

Issue: GREG-72

- Better loading of translations using suspense.
- Adds a "fetched" variable to the user objects. Enable us to show a
  spinner before the return of the userinfo call

Issue: GREG-72

The UserContext is used to "protect" routes

Issue: GREG-70