Modify permissions (local or global) for a particular group.

• If the admin is toggling views (from "simple" to "classic" or vice-versa), calls UpdateAdminPreferences in Subs-Admin.php
• Defaults to 'simple' permissions view if no admin preference is found
• Simply redirects to the main permissions area if you're trying to edit permissions for group 1 (Administrator)
• Assumes you're editing general permissions unless a profile ID is specified