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 filter customizations, 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.  Some needed changes are documented in recent migration guides and deprecation lists: 

• http://lucene.apache.org/core/2_9_4/api/core/deprecated-list.html
• https://lucene.apache.org/core/4_0_0/MIGRATE.html,
• https://lucene.apache.org/core/5_0_0/MIGRATE.html.

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

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