Actions are stored in a file called actions.tag in the diary directory.
Users preferences are stored in a file called '.taglog' under Unix,
or 'taglog.cfg' under Windows, both in the user's home directory. The preferences
file stores the projects the user books to, and can be used to override
the default preferences set in the program. The user preferences file must
be valid tcl script as it is sourced when the program starts.