NEXUS-5348: Purge Timeline task should remove persisted data too
Merge remote-tracking branch 'origin/master' into nexus-5348-purge-persist-data-too
NEXUS-5348: Made method usable in test
NEXUS-5348: Proper UT

That completely covers the purge case how files to
be deleted are collected.
NEXUS-5348: Applied comments
Merge pull request #67 from sonatype/nexus-5348-purge-persist-data-too

NEXUS-5348: purge persist data too