Set up admin automatically about quickfeed

[s111]

I think using agctl or just flipping the bool using sqlite3 is the best option. We could have the first user to register always be an admin. The only concern I have is the added complexity.

[meling]

All teachers will be admin in the sense that they can create courses etc. The first user to be admin will be responsible for promoting other teachers (at least the first other teacher) to admin role. So User.ID=1 has no special meaning except always being admin. So in CreateUserFromRemoteIdentity we can simply set IsAdmin:=true for the first user. This does not add much complexity IMO. Am I missing something @s111?

[s111]

No I don't think so, that's why I suggested having the first user always be an admin, as it's the least intrusive change.

[meling]

@s111 please review my commit 6caf767 ; can we close this issue?

[s111]

LGTM