adding v2 support to cinderclient

This will allow the cinderclient to speak to the v2 rest api if it's
enabled in the cinder config. Includes additional v2 tests as well.

blueprint cinderclient-v2-support

Change-Id: I004134d9f528a6eadefdaa89eb48087bcae2691f
v2 replaces display_name in response and args for name

Change-Id: I4e50e80346a48b9a7cefcea66ac228dade7e8ca4
Give volume details on creation of volume in v2

v2 rest api for volume creation gives a summary. This will fetch
additional information to give a proper detail view.

Change-Id: Ie1ea8de507a7d6e0430c8b74ddf87aec86af0046