Investigate the inconsistencies between embedded APICast and standalone apicast

WHY

APICast can be deployed via the 3scale operator, as one of many components, and via the APICast Operator. The method of deployment is different. For APICast within the the 3scale operator see this spec. For standalone APICast see this spec 

This difference can be confusing for customers who may use both apicast embedded and standalone and expect a similar usage pattern. 

WHAT

Catalog all the differences between both approaches and attempt to converge on a common and best practices approach for both, one example being, common handling of environment variables. 

Note, that some differences may be justifiable but these should be documented. 

DONE

The outcome of this Jira should be a catlog of differences and a proposal to converge. Where applicable, a justification on where the differences should remain and why.

An EPIC of follow on JIRAs to action the proposed items.