Adds an equivalent for "cinder get-pools" with "volume backend pool list"
and "cinder get-pools --detail" with "volume backend pool list --long".
Story: 1655624
Task: 136949
Signed-off-by: Sean McGinnis <sean.mcginnis@gmail.com>
Change-Id: I826c9946ffe11340d44ad57914f72fc2a72b6938