Create OS::Cinder::Volume and OS::Cinder::VolumeAttachment resources

This resource should share the same code as AWS::EC2::Volume but its properties schema should be derived from the Cinder REST volume creation API call.

According to the python-cinderclient volume create call, the following properties are elible for being in the resource properties schema for OS::Cinder::Volume (with equivalent AWS properties in parethesis)

size (Size)
snapshot_id (SnapshotId)
display_name
display_description
volume_type
availability_zone (AvailabilityZone)
status
attach_status
metadata (Tags)
imageRef
source_volid

FnGetAtt should expose any information that a look-up on the volume provides.

According to the python-cinderclient volume attachment call, the following properties are elible for being in the resource properties schema for OS::Cinder::VolumeAttachment (with equivalent AWS properties in parethesis)

volume_id (VolumeId)
instance_uuid (InstanceId)
mountpoint (Device)