1. There was scaleGatewayUp but no Down action
2. Gracefully remove node from etcd upon down-scale of nodes/gateways
3. Log to user which gateways were created/deleted
4. Deployment either hanged or worked incorrectly when downscaling and then
upscaling something again
Also sets minimum gateway node count to 1 until gateway-less mode be fully
functional again
Change-Id: Ie3255f70b8a3fdfadab119a579c00433938495c8
Closes-Bug: #1509074
9715d5e3e7