Do not run selinux commands if it is disabled.

 * Execution of the setenforce command when selinux was not enabled
   was resulting in a non-zero exit status, which halted devstack.
 * Addresses bug 1175444

Change-Id: I7f6492dea7c52d153e755cda826d6fabd53f3771
add support for changing cinder perodic_interval

As discovered in tempest, when you create and delete volumes
quickly, and have a small volume storage pool, you can get cinder
scheduler to think you are "out of space" when you are not.

This is because cinder scheduler updates free space on it's
periodic job, which defaults to 60 seconds. We need control over
that value for the devstack gate otherwise we regularly get
overruns if we run too many volume tests quickly.

Work around for bug 1180976

Expect that this will get removed later if cinder gets a more
efficient way to update the scheduler for freed resources.

Also, don't be completely stupid about setting defaults....

Change-Id: I20e52e66fcc94b224476cdd14c88bd6981b4e617
Merge "Do not run selinux commands if it is disabled."
Use --managed-save flag to virsh undefine

If a virtual machine has got a managed save image, it is not
possible to delete it using a plain 'virsh undefine' command.
While Nova doesn't use 'managed save', the libvirt-guests
init script or systemd service may have created one if the
user rebooted their host. Thus we devstack should pass the
--managed-save flag to virsh to ensure the VM's removal.

Change-Id: Id9b072a6dceeb4e179d2b6a25bbdfb559c299e95
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Avoid installing python-nose for RHEL6.

 * python-nose on RHEL isn't new enough to support Tempest.

Change-Id: I98107bf664a12f6252f74b4511e3228d511ff855
Merge "Avoid installing python-nose for RHEL6."