Adds the resume_guests_state_on_host_boot parameter to the
nova::compute class. When a compute node is restarted and having
this option set to true will ensure that any guests that were running
when the node was rebooted will be started up again.
Default value for the resume_guests_state_on_host_boot in the nova
code is False.
Change-Id: I8b7ba48c68aefa9e1fd7092e9e64b9567d138dcf