OAK-1858 Segment Explorer
 - properly close the store on exit
 - added option to run compaction, run the diff between 2 node states, and to trace the node store references to a specific file (wip)

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1601403 13f79535-47bb-0310-9956-ffa450edef68