InitSpecialCode
procedure InitSpecialCode (const Key : TKey; Value : LongInt; Expires : TDateTime; var Code : TCode);
InitSpecialCode creates and initializes a special code using Key, Value, and Expires.
Value is stored as part of the Code.
The resulting code is valid until the date stored in Expires is reached.
This routine is defined in the OnGuard unit. (as of 1.15 this routine has been moved to the OgUtil unit)