Foreman Maintain

Thought this could be a good use case to be handled in foreman_maintain.
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Cloned from: https://bugzilla.redhat.com/show_bug.cgi?id=1392500

Description of problem:
Due to https://bugzilla.redhat.com/show_bug.cgi?id=1317057 and pulp changes with /var/lib/pulp structure, upgrading from 6.1 to 6.2 leaves all except one subdir of:

/var/lib/pulp/working
    /var/lib/pulp/content/yum_repo_metadata_file/
    /var/lib/pulp/published/yum/master/

directories as orphaned, occupying even GBs of disk space. The directories shall be purged (with one exception) during Satellite / pulp upgrade, like KCS

https://access.redhat.com/solutions/2754891

suggests.

Version-Release number of selected component (if applicable):
- Sat 6.2 upgraded from 6.1
- pulp 2.8 upgraded from 2.6

How reproducible:
100%

Steps to Reproduce:
1. Install 6.1
2. sync some repos, publish some Content Views
3. Upgrade to 6.2
4. Remove the C.V.s
5. Run weekly cron job to clean orphaned content
6. grep for C.V. name in /var/lib/pulp directory tree

Actual results:
Some of the 3 dirs still contain subdirs with the deleted C.V. name

Expected results:
No such subdir