docker: Make remove more robust.

Tag could be deleted even if image is used by container.

Signed-off-by: Jiří Župka <jzupka@redhat.com>
docker: Changes subsubtest behavior and make subsubtest more verbose.

Subsubtests mix subsubtests steps now.
initialization of all tests
run once of all tests
postprocess of all tests

New subsubtests:
initializaiton 1. test
run once 1. test
postprocess 1.test

initializaiton 2. test
run once 2. test
postprocess 2.test

this behavior should be easier for developing subsubtests
and could be more predicable.

verbosity:
When test raise exception then Error message is logged to error log,
in addition, traceback of exception is logged to debug log.

When subsubtest raise known error then subsubtest fails but
rest of subsubtests in subtest group could continue.
Known error should be only error.AutotestError (TestFail, ..)

When subsubtest raise unknown error then subsubtest fails and
stops running whole subtest stops too.

Signed-off-by: Jiří Župka <jzupka@redhat.com>
docker: Adds docker-cli\rmi test

Signed-off-by: Jiří Župka <jzupka@redhat.com>
dockerconf: Fix docker configuration version.

Signed-off-by: Jiří Župka <jzupka@redhat.com>