Implements a TM4J back-end which merges topic maps from one or more other back-end implementations dynamically. This backend provides a read-only "view" onto a set of topic maps as if they had been merged.
Although the view created by this backend is read-only, the individual topic maps that make up the view are still accessible and can be modified with changes being reflected dynamically in the unified view.
NOTE: The dynamic merging is based on subject address and subject indicators only. No merging is done by BaseName.