could REPLACE_ME_ORG and REPLACE_ME_APP_NAME in Makefiles and skaffold.yaml

[ryandawsonuk]

I am wondering if these could be {{.ORG}} and {{.APP_NAME}} instead. If they could be parameterised like that then it would be easier to fork a jx-based repo and import it into another cluster under a different github account. I guess the downside would be if anyone wanted to run the skaffold files locally.