MINDEXER-72 introduced updater FSDirectoryFactory API

FSDirectoryFactory allows host application choose specific
FSDirectory implementation. Default behaviour did not change
and deletages to Lucene FSDirectory.open.



git-svn-id: https://svn.apache.org/repos/asf/maven/indexer/trunk@1461840 13f79535-47bb-0310-9956-ffa450edef68