Added Gazetteer interface and LuceneGazetteer implementation and tests to move gazetteer lookup functions out of the LocationResolver implementation.
Removed LocationResolver interface (the implementation of this interface IS CLAVIN; alternate implementations are a different package) and refactored LuceneLocationResolver into ClavinLocationResolver, depending on a Gazetteer implementation for location lookups.  Updated test classes and consumers of the old LocationResolver interface accordingly.
Added test classes for ClavinLocationResolver.