Add deployment docs for AWS NLB (#1785)

deploy/provider/aws/service-nlb.yaml

@@ -0,0 +1,23 @@
+kind: Service
+apiVersion: v1
+metadata:
+  name: ingress-nginx
+  namespace: ingress-nginx
+  labels:
+    app: ingress-nginx
+  annotations:
+    # by default the type is elb (classic load balancer).
+    service.beta.kubernetes.io/aws-load-balancer-type: nlb
+spec:
+  # this setting is t make sure the source IP address is preserved.
+  externalTrafficPolicy: Local
+  type: LoadBalancer
+  selector:
+    app: ingress-nginx
+  ports:
+  - name: http
+    port: 80
+    targetPort: http
+  - name: https
+    port: 443
+    targetPort: https