Fix Nginx lb in k8s/istio

Fix Nginx lb in k8s/istio

- Provide workaround to make nginx lb work properly
- nginx_client sample can modify default load balancing
from three to two servers at runtime
- Ensure port 9180 is used for default deploy for lb and
servers
- Modify render_yaml to specify deploy_name so that
clover-server1, 2, 3 can be used for default lb config
- Ensure proxy template is aligned to lb to allow the
source IP from originating host to be propagated to final
destination

- Fix default nginx proxy server_name to 'proxy-access-control'
and change default proxy destination to 'http-lb'
- Split lb service_type to 'lbv1' and 'lbv2' to provide an example
of how to modify the run-time configuration of the load balancer
after deployment - modify http-lb-v2 to use clover-server4/5 instead
of the defualt clover-server1/2/3 - modify http-lb-v1 to use
clover-server1/2 instead of 1/2/3
- Aligned pod IP retrival method with nginx_client.py

Change-Id: I73fa60a69c93ae1e82a477ef6283c00f67a21360
Signed-off-by: Eddie Arrage <eddie.arrage@huawei.com>