Update to lucene 4.9.0

This PR update from Lucene 4.1 to 4.9. Main goal is to benefit from Lucene bugfix & improvements. This also provides capability to later use nice new features like indexing one field in the document in the index (instead of reindexing the whole record), more facets options and configuration, SearchSuggestion, ...

Migration was mainly related to API changes in NRT and Facet module.

Thanks Jesse for helping on fixing tests.