Add NOVA_SHUTDOWN_TIMEOUT variable

This adds a variable to control the [DEFAULT]/shutdown_timeout
config in nova to control whether or not a guest should have
a graceful shutdown of the OS or if it should just stop
immediately (no timeout). Since devstack uses CirrOS images
by default, the default value for the NOVA_SHUTDOWN_TIMEOUT
variable is 0 which should speed up tempest runs. The default
in nova.conf [1] is 60 seconds.

[1] https://docs.openstack.org/nova/latest/configuration/config.html#DEFAULT.shutdown_timeout

Change-Id: Ida83f70a1c4e61e5248f2bd42b4c24f7ac6d2310
Related-Bug: #1829896
1 file changed