delete downloaded cartridge when component is deleted
Merge pull request #2741 from rajatchopra/master

Merged by openshift-bot
Merge pull request #2742 from sosiouxme/diagnostics

Merged by openshift-bot
<common> add oo-diagnostics and man page

* moving oo-diagnostics to rubygem-o-o-common to make available on all hosts.
* adding a man page for it