On compute shutdown we might want to gracefully shutdown instances
using libvirt-guests. If it gets configured is managed via a tht
parameter NovaResumeGuestsStateOnHostBoot. This triggers config
of /etc/sysconfig/libvirt-guests via puppet-nova, configures a
dependency for virt-guest-shutdown.target to
paunch-container-shutdown.service that instances get shutdown
before the libvirt container gets stopped.
Change-Id: Id1cc2e75af316b864cebf601395f1111b7fb049a
Closes-Bug: 1778216
Depends-On: I2766cdd66ff17756daaf1a75ad516a7af6eebddc