Refactor the prow/cmd Dockerfiles to use shared base Dockerfiles#4900

Merged

k8s-ci-robot merged 2 commits intokubernetes:masterfrom mattmoor:dockerfiles

Oct 5, 2017

+60-39

Commits on Oct 5, 2017

Refactor the Dockerfiles to use shared base Dockerfiles for common functionality
mattmoor
committed
Move image directories based on review feedback.
mattmoor
committed