Create `isAdminUser()` function

[aryanprince]

We would need a role column in our User table.

role can be an Enum with the following options: "STUDENT", "TEACHER", "ADMIN"

By default, let's set the 3 of us to "ADMIN"/"SUPERADMIN" and then every other user who signs up gets "GUEST"/"STUDENT" role by default.

Now when I call the function isAdminUser(), the function checks the database for the currently logged in user's role, and returns true / false if he's "ADMIN".

[lewisj576]

I'd like to do this.

[aryanprince]

@lewisj576 See the updated description now. Could you create a new issue just for "Creating the role column in DB" or sm

And then you would only work on this issue after implementing that?