Fix minor thinks in lots of tests. Mainly compatibility problems with new version docker

Important commit https://github.com/jzupka/autotest-docker/commit/0cb718dc5fbb30f6cd902ff88224561d6c73a1c0 fixes problem with generator of names.
I solved this one slightly differently.  IIRC, I made it so that ``None`` is an acceptable value for "repo".  Surprisingly not many tests broke and it actually helped uncover a few more problems.  There is a ``--all`` option to ``images`` subcommand now that will frequently show ``None`` named images, so maybe this is simply a value we can accept?