GitLab

All Dockerfile now: Merge multiple 'RUN' commands to slim images size; Replace 'ADD' with 'COPY' as per best practices;

Set ofs.tpc to /opt/eos/xrootd/bin/xrdcp; Merge multiple 'RUN' commands to slim more images size; Replace 'ADD' with 'COPY' as per best practices

Slim images size; Drop ubuntu disco Dockerfile; Drop 'ENV DEBIAN_FRONTEND noninteractive' in ubuntu bionic Dockerfile"

Rename container names and net-aliases to homogenize with the eos-on-k8s project (this keeps hostnames shorter, didn't do the other way around because in k8s deployment a suffix is added and long hostnames likely hit HOSTNAME_MAX)