Simplify and Update Operator Edge Cluster Service

[t-fine]

After testing the current nginx-operator service (created with operator-sdk version 0.17) yesterday I discovered it is no longer correctly being deployed by the cluster agent. This service is probably over complicated as it is and could use some much needed simplifications.

Current operator service: https://github.com/open-horizon/examples/tree/master/edge/services/nginx-operator

A possible simpler solution to model a new operator service off of (created by Glen Darling): https://github.com/TheMosquito/Operator_Helper

From Sanjeev:
While working with a user, I came across a situation where the user was looking for a simple example (hello world example) for edge cluster and mistakenly tried to deploy the hello world edge device example without creating an operator. Yes user should have read the document and do the right things in the order specified but this is how users think and do. Current nginx-operator example is much more sophisticated and simpler example would be helpful.