openshift: the initial pull-request
    
    A new subdirectory openshift/ which provides the initial set of
    ansible-based OpenShift deployment (using Makefile).  Some changes that
    were done:
    
    - signing in containers got several fixes so it finally works
    - distgit && distgit-httpd container images merged into one
    - distgit httpd port is now well-defined on 5001
    - docker-compose.yaml better documents the exposed ports
    - 'dnf install' commands in Dockerfiles are all done in one RUN command,
      ended by 'dnf clean all' to keep the images (the increment) as small
      as possible
    - frontend entrypoint is executed in /usr/share/copr/copr_foreground as
      the home dir (where 'cd' steps) might not be well defined
    - ansible, resalloc-aws and ssh is needed in the resalloc container for
      full VM spawning
    - several entrypoints fixes
    - migrate stuff into a rootless scenario
    - backend's nginx to accept connection from any hostname (== no
      server_name specified)
    - use /bin/tini wrapper, avoid using supervisord
    
    Merges: #2193