Change Nova configuration key 'libvirt_type' to 'virt_type'
Change Nova configuration key 'libvirt_type' to 'virt_type'

The configuration key 'libvirt_type' became 'virt_type' under the
[libvirt] section in nova.conf on Icehouse.

Change-Id: Ib6c4df9a518c8637b36ca1dff67fbbbdc2eb78e5
Closes-Bug: #1287878

kairoaraujo/openstack-manuals,saeki-masaki/openstack-manuals,Akasurde/openstack-manuals,openstack/openstack-manuals,AlekhyaMallina-Vedams/openstack-manuals,potsmaster/openstack-manuals,potsmaster/openstack-manuals,gongysh2004/openstack-manual,kairoaraujo/openstack-manuals,openstack/openstack-manuals,AlekhyaMallina-Vedams/openstack-manuals,saeki-masaki/openstack-manuals,openstack/openstack-manuals,AlekhyaMallina-Vedams/openstack-manuals,gongysh2004/openstack-manual,openstack/openstack-manuals,Akasurde/openstack-manuals