Assign course DONE! Visual presentation DONE!

- Note that the “Courses” Select contains all the courses that exists
in the courses-table.
- When you press on a role, connected to a person, all courses that are
assigned to this role, will be highlighted in the color LIGHTSKYBLUE.

OPTIONAL next step:
- whenever you press on a course in the Select, all roles associated to
this course, shows up in the roles table. That would be nice, to see
how many people, that are attending the specific course. BUT LETS WAIT
WITH THAT.

Commit: Christopher