Set live_migrate_paused_instances=True in tempest.conf

Live migration of paused instances is a new Nova feature in Kilo, and will not
be backported.  The compute_feature_enabled.live_migrate_paused_instances flag
defaults to False for this reason, but can be set to True here. The tempest
config option and this change can both be removed at Juno-EOL.

The related Tempest change: I5c6fd3de7ea45d1851bb40037c64ad7fb5e6dc48

Change-Id: I3a83e43d252b88c234438a224e2fbebc0a81eaff
Related-Bug: #1305062
diff --git a/lib/tempest b/lib/tempest
index cd8fbd7..6ce245a 100644
--- a/lib/tempest
+++ b/lib/tempest
@@ -364,6 +364,8 @@
     iniset $TEMPEST_CONFIG compute-feature-enabled api_extensions $compute_api_extensions
     # TODO(mriedem): Remove the preserve_ports flag when Juno is end of life.
     iniset $TEMPEST_CONFIG compute-feature-enabled preserve_ports True
+    # TODO(gilliard): Remove the live_migrate_paused_instances flag when Juno is end of life.
+    iniset $TEMPEST_CONFIG compute-feature-enabled live_migrate_paused_instances True
 
     # Network
     iniset $TEMPEST_CONFIG network api_version 2.0