Add user_managed: false to crowbar.yml.

Wayne told me to, that is why.
Merge pull request #6 from VictorLowther/pull-req-release-mesa-1.6-master-07ceb2b08754707807f05f279939d55b927a010a

https://github.com/crowbar/barclamp-dell_raid/pull/6

Merged by devtool for ArkadyKanevsky