OAK-1159: Backup and restore

Fix (and @Ignore) the blob duplication test case, it didn't really capture the problem so far
Improve the tarmk inspection output format.

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1547813 13f79535-47bb-0310-9956-ffa450edef68