Revert "* More debug output in FuzzyIndex."

This reverts commit 1d69880b317e92cfedba0d0ab45ca3f6c376049e.
Revert "* Re-added clucene cmake modules."

This reverts commit 3194c41981ceec2ceecae6771ca3c17e0f8b94d0.
Revert "* Revert to CLucene until we sort out the MinGW/Boost/Unicode mess :-("

This reverts commit 1e8bab26b22a20d4cc07c9b85c590a3d4f7f9c18.
* Keep m_luceneReader & -Searcher alive during indexing and don't block mutex while searching.
* Only allow one settings dialog at a time.
* Style fixes.