Remove a TODO item in engine service
Remove a TODO item in engine service

The node update logic is now all moved to action execution. This patch
removes a TODO comment from the engine source.

Change-Id: Icccc34a09833e1929a54ece16f6b2ed2d7c524c1

openstack/senlin,openstack/senlin,openstack/senlin,stackforge/senlin,stackforge/senlin,tengqm/senlin-container,tengqm/senlin-container