Implement the new IndexProvider SPI to store relevant configured indexes in Lucene 4.x. This will allow users to define specific indexes and say which (if any) should be stored in Lucene 4 on the local file system.
The provider should support full-text search indexes (full-node and specific property sets) and normal property indexes: STRING, LONG, DOUBLE, DATE, DECIMAL, URL, PATH. Support for REFERENCE, WEAKREFERENCE and SIMPLEREFERENCE would be lower priority. There is no need for BINARY properties (these will be handled via full-text search).