OAK-2194: Print tar file graph in segment explorer
explorer and debug run modes now also dump the tar file graph

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1632074 13f79535-47bb-0310-9956-ffa450edef68
minor improvement

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1632079 13f79535-47bb-0310-9956-ffa450edef68