Lucene Per-segment search

Per-segment searching is largely kept under the covers but since LexEVS employs a number of customizations of parameters, particularly filters many queries may break and need refactoring.  At the same time a number of objects have new names, apis and other changes that will require refactoring and updating to an as yet undetermined amount.

The use of IndexReader in particular will not change, but filters and queries passed into this may break or otherwise be unusable.  Read this article for more information: http://blog.thetaphi.de/2012/02/is-your-indexreader-atomic-major.html

Updated Objects will include

• ChainedFilter replaced with BooleanFilter
• HitCollector is replaced by Collector or SimpleCollector
• MultiSearcher will likely be replaced by something like IndexSearcher(MultiReader)
• The interface Searchable has gone away and it's former child classes such as IndexSearcher will have to take it's place.

Updated Objects that have new API's include:

• DocIdSetIterator
• Searcher
• IndexWriter
• IndexReader (optimizing methods can no longer be called on this.)
• TermsFilter (addTerm() method has gone away and a replacement may be needed.)