Different user templates per world

Right now, there’s a single user template that is shared across all worlds.

Creating a separate template per world would let us clean up the usre template, prevent bad references in script properties, and duplicate scripts across worlds as need be (for example, having a race per world wouldn’t work with a single user template that’s shared, but would with separate user templates per world).

As an addendum to this, it would probably be useful to have a SuperUser template that operates as the current User template does.