Show some of the more detailed help to give the admin an idea.
..
It shows a popup for administrative or user help.
It uses the help parameter to decide what string to display and where to get
the string from. ($helptxt or $txt?)
It is accessed via ?action=helpadmin;help=?.
uses ManagePermissions language file, if the help starts with permissionhelp.
uses Help template, popup sub template, no layers.