First pass at making Cinder use the disk claiming machinery.
Allow for switching to/from using eqlx, instead of it being a one-way switch.
Merge pull request #28 from VictorLowther/pull-req-release-pebbles-master-b33d4f791a3432f0d3d2d4ea58a1c80f9ce6c95e

https://github.com/crowbar/barclamp-cinder/pull/28

Merged by devtool for cloudsleuth