Investigate using buildah to build our images

[jlewi]

https://github.com/projectatomic/buildah

We use docker build to build all our images. This is convenient when building locally but its problematic when it comes to containerizing our build/test infrastructure and running on K8s clusters. Using docker inside containers requires privileged pods and mapping in the docker socket; which isn't ideal.

I think buildah might better support building container images from within a container. I think the one issue I heard but didn't quite understand was that you can't use overlayfs when building from within a container, you have to use a different storage layer and mount it from the host.

buildah is being developed by Red Hat and is used by their source to image tool for openshift.

[jlewi]

Argo seems like the most promising solution right now for docker builds.