Username
System user, Can create and administer links.
Min length 5, max length 32. Required.
Password
User password.
Min length 7, max length 64. Required.
User email.
Required.
Domain
Accepted domain(s) that user may log in from.
Max length 256. Optional. Defaults to any domain (*).
Confirm
User email has been confirmed.
Optional.
Active
User account is currently active or not.
Optional.
