Feature: Invitations by e-mail.

This lets us invite new users to the blog by e-mail. After a new user is created, a form is displayed with a subject line and message containing the user's access link. The administrator can then personalise the message if desired before it is sent to the new user.

It is possible to resend the invitation at any time. Users who have lost the access link can also request a reminder from the non-authentication page, where they can enter their e-mail address; if that address corresponds to a registered user then that user is sent a reminder by e-mail.