encapsulates access to the current office installation directory and
office user data directory, provides functionality to create URLs
containing relocatable (not absolute) references to the current office
installation directory and user data directory and vice versa.
This functionality is useful when data containing references to the
current office installation directory or user data directory must be made
persistent and re-read later. In many cases, storing the reference
directly would destroy the relocatability of an office installation and the
possibility to share one office user data directory among parallel office
installtions.