Allow configurable egress for server network policy

[corest]

There are specific cases when the server pod needs to communicate with some external components.
E.g. when using various auth backends:

• kubernetes - server needs to talk with k8s api
• github - server needs to talk with github

[jasonodonnell]

@corest Thanks for the contribution!

This use case makes sense but I wonder if we need to allow users to pass in whatever configurations they want for their egress.
For example, instead of egress being a boolean, we instead just take whatever YAML the operator wants to add. server.initContainers is a good example of this.

Using this design an operator can add whatever to rules they want for their environment and we don't need a bunch of very specific configurables.

Thoughts?

[corest]

@jasonodonnell agree
Added test for egress templation