aggregate AddNodesToLoadBalancer steps
Merge branch 'always-use-configured-lb' into batch-lb-adds
Merge branch 'always-use-configured-lb' into batch-lb-adds
Merge branch 'always-use-configured-lb' into batch-lb-adds
node_configs -> address_configs
lint
docstring for optimize_steps
indent better
Merge pull request #723 from rackerlabs/batch-lb-adds

Batch / aggregate Load Balancer adds in convergence [AS-398]