The hard-coded port 8400 in consul-examples-helper.sh should be 8500

[rberlind]

The hard-coded port 8400 in consul-examples-helper.sh should be 8500. While port 8400 used to be used in Consul as part of the RPC client interface, that was deprecated in consul 0.8 which began using HTTP and port 8500 for all CLI commands. See https://github.com/hashicorp/consul/blob/master/CHANGELOG.md#080-april-5-2017