Allows the administrator to edit the registration agreement, and choose whether it should be shown or not.

• Accessed by ?action=regcenter;sa=agreement in 1.1 and ?action=admin;area=regcenter;sa=agreement in 2.0
• Displays a warning if agreement.txt couldn't be found or isn't writable, and doesn't allow saving in such cases.
• Uses the Admin template and the edit_agreement sub template.
• Requires the admin_forum permission.
• Uses the edit_agreement administration area.
• Writes and saves the agreement to the agreement.txt file.
• Can be found in Admin.php in 1.0.x