Add registry prefix at starter apps import

[CEDDM]

Problem description: In our company, we use Harbor registry for our apps and also as a proxy for DockerHub images. When I want to import starter apps with the Kafka Docker file, I have to add Harbor prefix (such as my-harbor-host/dockerhub-proxy) in the names of the images before importing.

Solution description: It would be great if we had an option in the import shell command to add this prefix automatically. For example : app import --uri file:///mydir/myfile --registry my-harbor-host/dockerhub-proxy

[markpollack]

Thanks for the suggestion, we will look into how to make it easier to switch prefix to point to different registries.