Invite people when registration is disabled

[TobiasBales]

It would be nice to be able to invite people to Squash even when the global registration is disabled (primarily usefull for password login I think)
So one could disable registration but still add new team members.

Opinions on that?

[RISCfuture]

In order to do that, we'd need some sort of concept of a site admin. And some way of nominating a user to the role of site admin. Perhaps this is done in the database? Not sure the best way to do this.