manage-vdi: Wait until devices have been created before mounting

kpartx creates partition devices asynchronously - it may exit before
the devices have been created.  This may cause a subsequent mount call
to fail, because the device it is trying to mount does not yet exist.
kpartx now has a -s option which makes it wait for the devices to be
created before returning, but the version XenServer's dom0 doesn't have
this option.   Work around this by retrying the mount.

When dom0's kpartx is updated, we will be able to use the -s option.

Change-Id: I823a8eac4f3a2ef313d06e21da0f38ed46d7386a
Do not set os_aut_url for ceilometer

When install ceilometer with devstack, if do not set environment
variable OS_AUTH_URL, then devstack will set os_aut_url as empty
in /etc/ceilometer/ceilometer.conf, this will cause both
ceilometer-agent-central and ceilometer-agent-compute cannot start.

Fix bug 1205776

Change-Id: I32c77c92dc2e9d03c86e703f170e0216dd829a61
Merge "manage-vdi: Wait until devices have been created before mounting"
Merge "Do not set os_aut_url for ceilometer"