Ubercart Roles Integration

I'm running a membership site where a user can purchase certain roles. Depending on the role(s) that they put in their shopping cart this patch will correctly display only the appropriate fieldsets based on the Profile role rules.

Hope it makes sense. Normally Profile role cannot adjust the user registration form, but in this case it can. I made a patch incase this seems useful to anyone else. The patch is against 6.x-1.3.

Thanks!
Jamie.