OAM vs CNAB/Helm/kapitan

[xiang90]

When we describe OAM to our internal teams and potential customers, a frequent asked question is to compare OAM to CNAB/Helm/kapitan and how these technologies can work together.

I think we should clear out this confusion with a FAQ section either inside OAM spec repo or in its reference implementation repo or in the website.

/cc @resouer @hongchaodeng

[hongchaodeng]

We also need to clarify the parameters field and show how it is used with helm/kustomize.

[vturecek]

An FAQ section on the website seems like a good place for this.

[technosophos]

There is an FAQ for rudr that might answer this and other questions without us having to add a new document to this repo: https://github.com/microsoft/scylla/blob/master/docs/faq.md#how-does-this-compare-to-knative