Expose libvirt_cpu_mode parameter

Some users who are deploying OpenStack on nested hypervisors
(common in test lab environments) may wish to change the libvirt
CPU mode in nova.conf to expose CPU settings.  This setting is
now parameterized in the nova::compute::libvirt class.  This patch
exposes it via common.yaml.

Change-Id: I3d96c754e67343988831ddf949221ffd3a301281
Implements: blueprint expose-hw-virtualization
Expose libvirt disk_cachemodes setting

A recent change to the puppet-nova module allows users to specify
an array of settings to propagate into the disk_cachemodes setting
of nova.conf.  This change exposes the new capability to end users
so that those who need to tune IO settings can easily do so.  The
patch leaves the new setting commented out by default since this
will maintain the current behavior of puppet_openstack_builder with
regards to the disk_cachemodes setting in nova.conf (and since the
defaults are probably what most users will want).

Change-Id: I514182cbd1f107c9264c037ca6e3431b1e04bcc5
Implements: blueprint expose-disk-cachemodes
Add swift mappings for full_ha scenario

The full_ha scenario is missing several of the standard data mappings
required for swift. In addition, many of these mappings are different
than the default swift.yaml mappings due to the different topology of HA
environments.

Change-Id: Ie8bc5f5aaf32f33bbf188842367b1a9882956950
Closes-Bug: #1287927
Merge "Expose libvirt disk_cachemodes setting"
Merge "Expose libvirt_cpu_mode parameter"
Merge "Add swift mappings for full_ha scenario"
Merge remote-tracking branch 'origin/master' into coi-development