More changes to multi-node deployment guide

- Integrating changes suggested by Krish.
- Addressing comments on initial commit.

k8s/nginx-https/nginx-https-dep.yaml

@@ -1,17 +1,17 @@
 apiVersion: extensions/v1beta1
 kind: Deployment
 metadata:
-  name: ngx-https-instance-0-dep
+  name: ngx-instance-0-dep
 spec:
   replicas: 1
   template:
     metadata:
       labels:
-        app: ngx-https-instance-0-dep
+        app: ngx-instance-0-dep
     spec:
       terminationGracePeriodSeconds: 10
       containers:
-      - name: nginx-https
+      - name: nginx
         image: bigchaindb/nginx_https:1.0
         imagePullPolicy: IfNotPresent
         env: