Update version for Liberty
Update version for Liberty

Update the version for Liberty, switching from date-based versioning
to pre-versioning using SemVer. See
http://lists.openstack.org/pipermail/openstack-dev/2015-May/065211.html
and
http://lists.openstack.org/pipermail/openstack-dev/2015-June/067082.html
for details.

Change-Id: I6a35fa0dda798fad93b804d00a46af80f08d475c

scality/manila,sajuptpm/manila,jcsp/manila,scality/manila,weiting-chen/manila,NetApp/manila,bswartz/manila,openstack/manila,openstack/manila,NetApp/manila,vponomaryov/manila,weiting-chen/manila,jcsp/manila,bswartz/manila,redhat-openstack/manila,sajuptpm/manila,redhat-openstack/manila,vponomaryov/manila