Fix#63
**Requirements**
On supervisor's start page, a overview of the projects being supervised is shown as a table. One of columns is a flag and on clicking action the browser is redirected to forum page of that project.
Two improvements were asked:
1. If there is unread messages, show a tooltip if mouse is placed over the flag.
2. A number is shown to indicate number of unread messages.
**How to test**
1. Go to https://scipro-3470-forum-msg-ui-improvement.branch.dsv.su.se/
2. Log in as `eric@example.com`
3. Go to the project overview
4. Write something in the forum
5. Mark as unread (click the flag)
6. Go back to overview
Co-authored-by: Andreas Svanberg <andreass@dsv.su.se>
Reviewed-on: #61
Reviewed-by: Andreas Svanberg <andreass@dsv.su.se>
Tom Zhao
adf45414d5