[epic] let atomicapp modify provider configs

[goern]

Problem Statement

While deploying OpenShift configuration, it may be required to modify OpenShift's Security Context Constraints. This cant be done via oc create or some equivalent REST API call. Additionally there is no syntax within a Nulecule file to declare these SCC. See Grant Access to the Privileged SCC for an example.

Proposal

1. Document the current limitations of artifacts/ - what provider specific configuration may be part of an Atomic App and which provider configuration can not be modified via Atomic App.
2. research a the likelihood of the use case backing the Problem Statement
3. define syntax to define SCC as Nulecule Requirements and propose how Atomic App will evaluate and deploy these new type of requirements.

Rational

It is very likely that a Kubernetes or OpenShift based application will require more configuration than what Atomic App can deploy by today. Granting access to secrets (for example for github) is a common use case.