0.9.1 released

This is mainly a maintenance release, fixing many bugs found in 0.9, including eof exceptions, out-of-memory errors, and corrupted database files. It also contains further performance optimizations with respect to indexing and querying speed. New features include the highlighting of search terms in query results, simpler database startup, access to index information, new Cocoon examples, and an IzPack-based installer. For a complete list of changes see changes.xml.