Merge pull request #19 from crowbar/release/pebbles/master

pull changes from dell
if user specifies raw not local and there are no disks available I expect it to fails and return some sensible error, like " no raw storage available". It should not automatically switch to a different mode that is not specified by user
Merge pull request #53 from MirantisDellCrowbar/release/pebbles/unstable/master

Disable fallback to "local" storage when there is no disks available