User interfaces for querying indices.

Most classes in this package are just suggestions or experiments. The {@link it.unimi.di.mg4j.query.Query} tool lets you query one or more indices on the command line or possibly using a browser. The displayed results can be linked to actual data (files, collections, etc.) using items such as {@link it.unimi.di.mg4j.query.GenericItem} or {@link it.unimi.di.mg4j.query.FileSystemItem}.