Correct host aggregate and availability zone info
Correct host aggregate and availability zone info

The documentation around the creation of host aggregates and
availability zones. In particular indicating that a host could be in
multiple availability zones.

Change-Id: I56ea99cfe004b58ed903702b20896c479fa43644
Closes-Bug: #1433673

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