evacuate_all_instances:
This option will allow operators to decide whether all instances
or only those instances which are "HA_Enabled" should be allowed
for evacuation from a failed source compute node.
process_all_instances:
This option will allow operators to decide whether all instances
or only those instances which are "HA_Enabled" should be taken
into account to recover from instance_failure events.
Implements: blueprint ha-enabled-config-options
Change-Id: I9998295f03e7663f1da79fe5024b1a7553355ac2